Tuning with the EBL
03-18-2011, 03:16 PM
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Re: Tuning with the EBL
The ve is. Good 110 blm is when its loaded up.
My steps are at 32 at idle. D/c is 3 now so what Iac table effects the idle at operatiing temp to lower the steps down.
My steps are at 32 at idle. D/c is 3 now so what Iac table effects the idle at operatiing temp to lower the steps down.
03-18-2011, 03:37 PM
#1402
Re: Tuning with the EBL
110 is not a good BLM. It could be perfect 128 everywhere cept in that idle cell and
those cells immedately adjacent.
As you stated many IAC constants/tables. Lets disregard the constants and go to tables.
The ones I use are stall saver, power up initial, idle speed park, idle speed drive, minimul steps( I have 4.0). For park drive you command the rpm desired for each coolant temp. It uses IAC to hit that number. Say I command 700 for idle and it is showing on tach 750. I might try 650 commanded in table.
those cells immedately adjacent.
As you stated many IAC constants/tables. Lets disregard the constants and go to tables.
The ones I use are stall saver, power up initial, idle speed park, idle speed drive, minimul steps( I have 4.0). For park drive you command the rpm desired for each coolant temp. It uses IAC to hit that number. Say I command 700 for idle and it is showing on tach 750. I might try 650 commanded in table.
03-18-2011, 03:53 PM
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Re: Tuning with the EBL
RBob.
03-18-2011, 03:58 PM
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Re: Tuning with the EBL
The blm sits close to 128 within a few numbers so ve I'm sure its fine. I. Am courious why I have 24 IAC at 184 degs f I'm trying to find how u guys are getting 4 or 5. I am looking for the table to adjust the IAC lower at idle at operating temp.
03-18-2011, 04:05 PM
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Re: Tuning with the EBL
With the EBL P4 the knock filter has various options. We don't include one with the system, it is up to the user to decide which way to go regarding the knock filter.
Many don't use an ESC system as the engine has too much mechanical noise. Too much false knock, and is easily disabled in the calibration.
The other options for a EBL P4 knock filter is:
a) Use of a MEMCAL (protrudes from case)
b) Use of a plug-able knock filter such as from a 3.4l f-body, or an LT1 or LT4 filter (fits inside of case)
c) Use of a knock filter from a MEMCAL. User must solder to EBL board (fits inside of case)
d) Use of an external knock filter. This is such as the units used on TBI vehicles and early ('86-'89) TPI vehicles
In the case of 'c', if a user sends us the MEMCAL we can do the install onto the EBL P4 board.
When the EBL P4 was being designed we decided that it would be best if a MEMCAL was not required. Hence the on-board jumper for cylinder select and options for a knock filter. The V8 MEMCALs are hard to find and end up being costly when found.
However, with the EBL board mounted MEMCAL style knock filter, a filter can be removed from a myriad of 5.0, 5.7L or 7.4l truck MEMCALs and soldered onto the P4 board. This makes them readily available.
Along with the plug-able type used in the LT4 y-body's.
RBob.
03-18-2011, 04:10 PM
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Re: Tuning with the EBL
Its been an ongoing problem. I started working on the Map and TPS AE to get rid of the flat spots at acceleration from a stop. The loading up is irregular. Sometimes its all smooth and sometimes it loads up and stumbles...
03-18-2011, 04:23 PM
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Re: Tuning with the EBL
Ive tuned out most of the flat spots using the: AE- MAP PW & AE-TPS PW I ended up lowering the AE-TPS and bumping up the AE-Map. seems to be getting there nicely.
Now Sometimes it seems to load up at Idle. When I start out I hit around 110 in mt BLM and it stumbles and falls flat until I gun it. This only happens every so often. Not always Mostly it seems to do well. I have read that adjusting the IAC Steps allowing less air to pass through it and use more of the Fuel thats on the Throttle Plates.
There are 16 IAC Tables....So, what one do I start with or combination?
IAC - Minimum Idle Steps (possible this one)?
This table defines the steps used for the minimum idle steps position adjustment
Now Sometimes it seems to load up at Idle. When I start out I hit around 110 in mt BLM and it stumbles and falls flat until I gun it. This only happens every so often. Not always Mostly it seems to do well. I have read that adjusting the IAC Steps allowing less air to pass through it and use more of the Fuel thats on the Throttle Plates.
There are 16 IAC Tables....So, what one do I start with or combination?
IAC - Minimum Idle Steps (possible this one)?
This table defines the steps used for the minimum idle steps position adjustment
My IAC is at 22 when at Operating temp. 185 F.
My D/C is Now at 3(my throttle plates are closed to achieve the 3)
My BLM at idle in closed loop is very near 128.
Some times I Load up while Idling. Then it stays like that untill I burn it off. It hits blm of 110(Only due to the loading up).
I have now learned that it may be due to miss adjusted throttle plates and IAC not being correct.
Thats what I want to focus on.
Scott
Last edited by skerlock; 03-18-2011 at 04:37 PM.
03-19-2011, 09:53 AM
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Re: Tuning with the EBL
22 isn't terrible, and it's dynamic so it'll change as idle speed drifts. I typically see +/- 5 at "steady" idle, more or less. Some guys like 10, some like 15. In any case, low enough to cause fuel shearing at the throttle plates, and high enough to have some range to control idle if the idle speeds up for whatever reason.
DC is not determined by throttle plates. It'd determined by a combination of things. O2 sensor, VE, BLM, choke, etc. It's above 2, so methinks it's in a controllable range. Nothing to be too concerned about, probably. ( I could be wrong )
*IF* you had a duty cycle trying to go 0-1 AND a low BLM, suggesting that the ECM is still trying to reduce fuel from a 0 duty cycle, that would be a problem, and cause a very erratic idle, stalling, and general loss of control at that range.
DC and BLM are NOT determined at idle by throttle plate adjustment !!
DC ( or more correctly micro-seconds of open time ) is determined by the commanded AFR, and a guess at how much air is being pumped through the engine. A VE look-up, modified by choke, coolant temp, etc.
BLM is determined by the O2 sensor report, and the attempted correction applied to the DC, because the O2 is telling the ECM that the VE entry is wrong at this particular moment, for this particular temperature, etc. ( not that it's "wrong" per se, but that it's not exactly perfect at this moment under these conditions of humidity, temperature, and such )
The ECM adjusts the IAC based on the current RPM. Is the engine idling too fast ?
If so, too much air. The ECM can't control throttle plates, so reduce the IAC steps. Is it idling too slow ? Not enough air. The ECM can't open the throttle, but it can open the IAC, so Increase the steps. NO MATTER WHAT THE THROTTLE IS, the ECM can only compensate with the IAC. The throttle is closed, as far as the stop screw will let it close, so use the IAC to adjust air flow, based entirely on whether or not the present RPM is above or below the commanded idle RPM.
If the idle goes really too slow, look up stall saver settings, ignore everything else, and apply stall saver settings. Then start looking at RPM, O2, and such again.
In general, the IAC steps at idle are not determined by a table ! They are determined by the present RPM vs the commanded RPM.
If the log shows too many IAC steps when the engine is idling OK, then the throttle is closed too much. Turn the screw and open the throttle. The ECM will compensate by reducing the IAC steps to keep the air flow the same at that RPM.
( if IAC is already at zero, it'll start retarding spark to reduce RPM )
If the log ( or WUD display in "real time" ) shows not enough IAC steps, then close the throttle by turning the idle stop screw until the IAC steps increase to the desired number. ( roughly 5 in my case )
Some times I Load up while Idling. Then it stays like that untill I burn it off. It hits blm of 110(Only due to the loading up)
If you do nothing at all, does it surge and correct, or does it stall ?.Does the injector DC go to zero even momentarily ?
I have now learned that it may be due to miss adjusted throttle plates and IAC not being correct.
Thats what I want to focus on.
Thats what I want to focus on.
I don't think it's off far enough to be that much of a problem.
Once you have it set ( roughly 5 at operating temperature on an "average" day ) you'll see it range from zero to 15 or so over time, more or less.
Some days I see zero, with idle speed controlled entirely by spark ( and a resulting, not a cause, "wild" BLM ) Some days I see 30, and the IAC chasing idle RPM as it should.
Remember, as a rule of thumb, the BLM is NOT a result of RPM or throttle position. It's a result of the O2 sensor and the commanded AFR. ( and VE table )
IAC is a result of RPM and MAP. ( and by inference, CFM of air flow at the moment )
03-20-2011, 06:17 PM
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Re: Tuning with the EBL
Great Info Cflick.....I worked with my throttle plates and have a 5-6 IAC at operating Temp on Idle. Ill keep working from all the suggestions and let you know.Idle is surging at times. I raised the Park IAC speed +50 rpm and the drive/nut Iac rpm also. Ill look at the pulse rate in the map ae and TPS ae since ive been messing with those prior to the IAC
Thank You,
Scott
Thank You,
Scott
Last edited by skerlock; 03-20-2011 at 06:25 PM.
03-21-2011, 04:44 PM
#1415
Re: Tuning with the EBL
[QUOTEIdle is surging at times.][/QUOTE]
Consider making values for SA the same around that cell you desire to idle in. That way if rpm or map changes, placing in an adjacent SA cell it will see same SA.
Also try raising or lowering idle SA constant to see how engine likes it. I think I started with 24 deg SA and ended up with 17. Engine seemed to like 17.
Consider making values for SA the same around that cell you desire to idle in. That way if rpm or map changes, placing in an adjacent SA cell it will see same SA.
Also try raising or lowering idle SA constant to see how engine likes it. I think I started with 24 deg SA and ended up with 17. Engine seemed to like 17.
03-21-2011, 06:47 PM
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Re: Tuning with the EBL
Are you talking about the Idle State SA In The Scalers ?
Last edited by skerlock; 03-21-2011 at 06:53 PM.
03-22-2011, 09:16 AM
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Re: Tuning with the EBL
I lowered my SA-Main 1 degree and seemed to smooth it out.
Now I need to figure out why I get that heavy stumbling(Rich condition) on occasion when Im accelerating from a stop. It only happens occasionally. I will run some data logs today and post them later. Im wondering if Im having an Intermittent problem with the signal to my injectors.
RBOB Can this be related to the fuel Not returning fast enough to the tank? I remember when I first talked to you when I was purchasing your system That you had mentioned a guy the put in a fuel pump too large flow (a 255 LPH) in and had problems with the fuel backing up at the TBI. Im running the 190 LPH pump at 22 psi.
Regards,
Scott
Now I need to figure out why I get that heavy stumbling(Rich condition) on occasion when Im accelerating from a stop. It only happens occasionally. I will run some data logs today and post them later. Im wondering if Im having an Intermittent problem with the signal to my injectors.
RBOB Can this be related to the fuel Not returning fast enough to the tank? I remember when I first talked to you when I was purchasing your system That you had mentioned a guy the put in a fuel pump too large flow (a 255 LPH) in and had problems with the fuel backing up at the TBI. Im running the 190 LPH pump at 22 psi.
Regards,
Scott
03-22-2011, 09:32 AM
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Re: Tuning with the EBL
I lowered my SA-Main 1 degree and seemed to smooth it out.
Now I need to figure out why I get that heavy stumbling(Rich condition) on occasion when Im accelerating from a stop. It only happens occasionally. I will run some data logs today and post them later. Im wondering if Im having an Intermittent problem with the signal to my injectors.
RBOB Can this be related to the fuel Not returning fast enough to the tank? I remember when I first talked to you when I was purchasing your system That you had mentioned a guy the put in a fuel pump too large flow (a 255 LPH) in and had problems with the fuel backing up at the TBI. Im running the 190 LPH pump at 22 psi.
Regards,
Scott
Now I need to figure out why I get that heavy stumbling(Rich condition) on occasion when Im accelerating from a stop. It only happens occasionally. I will run some data logs today and post them later. Im wondering if Im having an Intermittent problem with the signal to my injectors.
RBOB Can this be related to the fuel Not returning fast enough to the tank? I remember when I first talked to you when I was purchasing your system That you had mentioned a guy the put in a fuel pump too large flow (a 255 LPH) in and had problems with the fuel backing up at the TBI. Im running the 190 LPH pump at 22 psi.
Regards,
Scott
As for the intermittent rich, maybe a bad spot in the TPS? Getting a data log of it will help in determining what is going on.
RBob.
03-22-2011, 04:04 PM
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Re: Tuning with the EBL
Bob,
I sent the Dat log to your e-mail at dynamic efi. keep in mind that What you are seeing is while its doing it while driving. It may be directly related to temp. this is happening before it is at operating temp now that im looking closer at it.
I sent the Dat log to your e-mail at dynamic efi. keep in mind that What you are seeing is while its doing it while driving. It may be directly related to temp. this is happening before it is at operating temp now that im looking closer at it.
Last edited by skerlock; 03-22-2011 at 04:23 PM.
03-23-2011, 10:26 AM
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Re: Tuning with the EBL
When data logging tap the space bar when the stumbling (or other issue) occurs. Doing so places markers in the data log. They show up as green highlighted lines in the analysis display and graph.
RBob.
03-23-2011, 05:10 PM
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Re: Tuning with the EBL
^^Then use your AE-RPM, AE-Filter tables, even delta scalars to adjust AE.
Edited:
ie. AE-PW is first adjusted for pressure compensation, then use the modifiers listed above, finally if you find a need to modify the curve (usually for hot cams) further tweaking of the AE-PW tables may be necessary.
Edited:
ie. AE-PW is first adjusted for pressure compensation, then use the modifiers listed above, finally if you find a need to modify the curve (usually for hot cams) further tweaking of the AE-PW tables may be necessary.
Last edited by xch3no2; 03-24-2011 at 02:53 PM.
03-24-2011, 05:37 PM
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Re: Tuning with the EBL
How can I see what my BLM(Air Fuel Ratio) is when I'm in AE and PE. My understanding is that when in AE or PE VE learn stops and the Blm reading on the whats up display stops reading until the PE or AE light goes out. Correct?
Scott
Scott
03-24-2011, 07:09 PM
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Re: Tuning with the EBL
The BLM freezes if richer than stoich, and that reference is used to calculate the fuel required to achieve the commanded AFR.
If leaner, it's returned to 128, and the current table entries are used, to avoid mistakenly calculating something leaner than commanded.
If incorrect, richer is safer.
Remember, the narrow band can determine richer than stoich, but is completely incapable of determining how much richer, even approximately.
03-25-2011, 10:19 AM
#1427
Re: Tuning with the EBL
BLM has little relationship to A/F ratio. BLM is adding or subtracting fuel to achieve stoich.(14.3/1 E10). BLM of 135 is stoich. It is just adding fuel. 120 is also stoich just pulling fuel to arrive at stoich. To see A/F you need a WB. whether in CL OL or AE or PE. VE Learn is off when in modes you mentioned as well as OL. If using WB as a substitute for NB I believe VELearn will Learn for PE commanded A/F.
03-25-2011, 10:27 AM
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Re: Tuning with the EBL
NEVER MIND I JUST FOUND IT...Sorry...WB = wideband uses the 3 wire O2 sensor? and WB stands for? Ive read about some adding a 3 Wire to their 1 wire system...Doable? and worth it?
Define(stoich) Gas stoichiometry is the quantitative relationship (ratio) between reactants and products in a chemical reaction with reactions that produce gases. Gas stoichiometry applies when the gases produced are assumed to be ideal, and the temperature, pressure, and volume of the gases are all known.
Fuel By mass
Gasoline 14.7 : 1
Define(stoich) Gas stoichiometry is the quantitative relationship (ratio) between reactants and products in a chemical reaction with reactions that produce gases. Gas stoichiometry applies when the gases produced are assumed to be ideal, and the temperature, pressure, and volume of the gases are all known.
Fuel By mass
Gasoline 14.7 : 1
Last edited by skerlock; 03-25-2011 at 10:34 AM.
03-25-2011, 01:17 PM
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Re: Tuning with the EBL
Last edited by xch3no2; 03-25-2011 at 02:12 PM.
03-25-2011, 01:40 PM
#1430
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Re: Tuning with the EBL
aem sells a good one also with 6 interchangable faces , i had one of those in my srt4 . i bought a shiftglow an the sencer took a dump after 2 months
03-29-2011, 12:06 PM
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Re: Tuning with the EBL
Ok here are my VE's combined. I reset my AE PW Map and TPS using what Rob suggested in an earlier post. I haven't changed my VE in the areas that are Outside the driving Im doing(ve learns).
The learns are well balanced. Im going to lower my AE PW TPS due to me still having that rich condition. It only happens when Im not at Operating Temp. I am NOT going to touch the AE-MAP.
I am still hitting 100% in VE but it only wants 1 or 2 Higher I may not worry about it.
The learns are well balanced. Im going to lower my AE PW TPS due to me still having that rich condition. It only happens when Im not at Operating Temp. I am NOT going to touch the AE-MAP.
I am still hitting 100% in VE but it only wants 1 or 2 Higher I may not worry about it.
Last edited by skerlock; 03-29-2011 at 12:23 PM.
03-29-2011, 01:17 PM
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Re: Tuning with the EBL
I was kind of curious about the IAC steps myself. So far they've dropped to 0... I'm assuming I can close the throttle blades a little more? Even when I have them completely closed it wants to drop to 0, though the lowest 'Minimum Idle Steps' setting is at 18. Am I missing something or is there something else I need to adjust?
03-29-2011, 01:51 PM
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Re: Tuning with the EBL
I think as long as you can maintain 1.5mm clearance from blade to bore it's ok to close them.
03-29-2011, 01:54 PM
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Re: Tuning with the EBL
Almost.
22 isn't terrible, and it's dynamic so it'll change as idle speed drifts. I typically see +/- 5 at "steady" idle, more or less. Some guys like 10, some like 15. In any case, low enough to cause fuel shearing at the throttle plates, and high enough to have some range to control idle if the idle speeds up for whatever reason.
DC is not determined by throttle plates. It'd determined by a combination of things. O2 sensor, VE, BLM, choke, etc. It's above 2, so methinks it's in a controllable range. Nothing to be too concerned about, probably. ( I could be wrong )
*IF* you had a duty cycle trying to go 0-1 AND a low BLM, suggesting that the ECM is still trying to reduce fuel from a 0 duty cycle, that would be a problem, and cause a very erratic idle, stalling, and general loss of control at that range.
DC and BLM are NOT determined at idle by throttle plate adjustment !!
DC ( or more correctly micro-seconds of open time ) is determined by the commanded AFR, and a guess at how much air is being pumped through the engine. A VE look-up, modified by choke, coolant temp, etc.
BLM is determined by the O2 sensor report, and the attempted correction applied to the DC, because the O2 is telling the ECM that the VE entry is wrong at this particular moment, for this particular temperature, etc. ( not that it's "wrong" per se, but that it's not exactly perfect at this moment under these conditions of humidity, temperature, and such )
The ECM adjusts the IAC based on the current RPM. Is the engine idling too fast ?
If so, too much air. The ECM can't control throttle plates, so reduce the IAC steps. Is it idling too slow ? Not enough air. The ECM can't open the throttle, but it can open the IAC, so Increase the steps. NO MATTER WHAT THE THROTTLE IS, the ECM can only compensate with the IAC. The throttle is closed, as far as the stop screw will let it close, so use the IAC to adjust air flow, based entirely on whether or not the present RPM is above or below the commanded idle RPM.
If the idle goes really too slow, look up stall saver settings, ignore everything else, and apply stall saver settings. Then start looking at RPM, O2, and such again.
In general, the IAC steps at idle are not determined by a table ! They are determined by the present RPM vs the commanded RPM.
If the log shows too many IAC steps when the engine is idling OK, then the throttle is closed too much. Turn the screw and open the throttle. The ECM will compensate by reducing the IAC steps to keep the air flow the same at that RPM.
( if IAC is already at zero, it'll start retarding spark to reduce RPM )
If the log ( or WUD display in "real time" ) shows not enough IAC steps, then close the throttle by turning the idle stop screw until the IAC steps increase to the desired number. ( roughly 5 in my case )
It should self correct. BLM dropping to 110 suggests it's trying to do exactly that.
If you do nothing at all, does it surge and correct, or does it stall ?.Does the injector DC go to zero even momentarily ?
I kinda doubt it, now that we know where your IAC is at idle.
I don't think it's off far enough to be that much of a problem.
Once you have it set ( roughly 5 at operating temperature on an "average" day ) you'll see it range from zero to 15 or so over time, more or less.
Some days I see zero, with idle speed controlled entirely by spark ( and a resulting, not a cause, "wild" BLM ) Some days I see 30, and the IAC chasing idle RPM as it should.
Remember, as a rule of thumb, the BLM is NOT a result of RPM or throttle position. It's a result of the O2 sensor and the commanded AFR. ( and VE table )
IAC is a result of RPM and MAP. ( and by inference, CFM of air flow at the moment )
22 isn't terrible, and it's dynamic so it'll change as idle speed drifts. I typically see +/- 5 at "steady" idle, more or less. Some guys like 10, some like 15. In any case, low enough to cause fuel shearing at the throttle plates, and high enough to have some range to control idle if the idle speeds up for whatever reason.
DC is not determined by throttle plates. It'd determined by a combination of things. O2 sensor, VE, BLM, choke, etc. It's above 2, so methinks it's in a controllable range. Nothing to be too concerned about, probably. ( I could be wrong )
*IF* you had a duty cycle trying to go 0-1 AND a low BLM, suggesting that the ECM is still trying to reduce fuel from a 0 duty cycle, that would be a problem, and cause a very erratic idle, stalling, and general loss of control at that range.
DC and BLM are NOT determined at idle by throttle plate adjustment !!
DC ( or more correctly micro-seconds of open time ) is determined by the commanded AFR, and a guess at how much air is being pumped through the engine. A VE look-up, modified by choke, coolant temp, etc.
BLM is determined by the O2 sensor report, and the attempted correction applied to the DC, because the O2 is telling the ECM that the VE entry is wrong at this particular moment, for this particular temperature, etc. ( not that it's "wrong" per se, but that it's not exactly perfect at this moment under these conditions of humidity, temperature, and such )
The ECM adjusts the IAC based on the current RPM. Is the engine idling too fast ?
If so, too much air. The ECM can't control throttle plates, so reduce the IAC steps. Is it idling too slow ? Not enough air. The ECM can't open the throttle, but it can open the IAC, so Increase the steps. NO MATTER WHAT THE THROTTLE IS, the ECM can only compensate with the IAC. The throttle is closed, as far as the stop screw will let it close, so use the IAC to adjust air flow, based entirely on whether or not the present RPM is above or below the commanded idle RPM.
If the idle goes really too slow, look up stall saver settings, ignore everything else, and apply stall saver settings. Then start looking at RPM, O2, and such again.
In general, the IAC steps at idle are not determined by a table ! They are determined by the present RPM vs the commanded RPM.
If the log shows too many IAC steps when the engine is idling OK, then the throttle is closed too much. Turn the screw and open the throttle. The ECM will compensate by reducing the IAC steps to keep the air flow the same at that RPM.
( if IAC is already at zero, it'll start retarding spark to reduce RPM )
If the log ( or WUD display in "real time" ) shows not enough IAC steps, then close the throttle by turning the idle stop screw until the IAC steps increase to the desired number. ( roughly 5 in my case )
It should self correct. BLM dropping to 110 suggests it's trying to do exactly that.
If you do nothing at all, does it surge and correct, or does it stall ?.Does the injector DC go to zero even momentarily ?
I kinda doubt it, now that we know where your IAC is at idle.
I don't think it's off far enough to be that much of a problem.
Once you have it set ( roughly 5 at operating temperature on an "average" day ) you'll see it range from zero to 15 or so over time, more or less.
Some days I see zero, with idle speed controlled entirely by spark ( and a resulting, not a cause, "wild" BLM ) Some days I see 30, and the IAC chasing idle RPM as it should.
Remember, as a rule of thumb, the BLM is NOT a result of RPM or throttle position. It's a result of the O2 sensor and the commanded AFR. ( and VE table )
IAC is a result of RPM and MAP. ( and by inference, CFM of air flow at the moment )
03-29-2011, 07:18 PM
#1436
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Car: '92 GMC C1500 RCSB
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Re: Tuning with the EBL
At operating temperature idle speed is at 500 park/575 drive. Currently the IAC goes to 0 no matter what I've tried at idle. Spark advance is 4º, but my initial is 8º, so I'm making an assumption it's running 12º? I'm not 100% sure there though.
Another thing is I've had to run it open loop since I put the engine in, otherwise DC drops to 0 and the engine stalls (I've already zeroed out the async table). Should using the set screw to open the blades slightly help with this as well?
Another thing is I've had to run it open loop since I put the engine in, otherwise DC drops to 0 and the engine stalls (I've already zeroed out the async table). Should using the set screw to open the blades slightly help with this as well?
03-29-2011, 08:00 PM
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Re: Tuning with the EBL
More info so we don't have to go back & look for it.
F/P, inj size, BPC, WB readings, are the BLM/INT taking a dive?
Need to be real sure about vac leaks (throttle shaft?) & correct & properly functioning PCV.
F/P, inj size, BPC, WB readings, are the BLM/INT taking a dive?
Need to be real sure about vac leaks (throttle shaft?) & correct & properly functioning PCV.
Last edited by xch3no2; 03-29-2011 at 08:12 PM.
03-29-2011, 09:03 PM
#1438
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Re: Tuning with the EBL
25psi, 80lb. injectors, BPC is 82, I'm not sure about vacuum leaks (never really checked because I can get it to idle stock-smooth but it goes rich - about 13:1), and I haven't really looked at BLMs but while driving 95%+ of it is pretty much spot on (learns are down to 2-5% correction depending on outside temperature, etc.).
03-29-2011, 10:23 PM
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Re: Tuning with the EBL
It's very easy to over-fuel the idle @ 25psi w/80pph injectors.
It's hard to get the big picture on snipits of info. Is the idle PW falling below 1.2ms?
The big injectors loose control below that, I thought you had 17084304 (75pph) injectors?
How high are your VE #'s ?
Do you have a vrfpr you can employ?
So where I'm going with this,...is the IAC running low to keep the idle speed down with an excess of fuel? If your not making 90 on the VE I would consider dropping the fuel pressure slightly. Let us know.
It's hard to get the big picture on snipits of info. Is the idle PW falling below 1.2ms?
The big injectors loose control below that, I thought you had 17084304 (75pph) injectors?
How high are your VE #'s ?
Do you have a vrfpr you can employ?
So where I'm going with this,...is the IAC running low to keep the idle speed down with an excess of fuel? If your not making 90 on the VE I would consider dropping the fuel pressure slightly. Let us know.
Last edited by xch3no2; 03-29-2011 at 11:12 PM.
03-30-2011, 09:13 AM
#1442
Re: Tuning with the EBL
My point in asking the RPM commanded was to determine if IAC is dropping to zero that could mean it cannot achieve that idle RPM which I think is a bit low. It has to set IAC steps to zero. At that point it cannot reduce any further. If the throttle bades are closed too far it will die.
80 lbs at 25 lbs FP is a lot of fuel. How did you DETERMINE that need on inj size and FP?
Before I had a VAFPR I had 80's at 20 lbs and my DC fell to minimums and stall save would cause a surge. Not sure if engine died. Also I idle synch as asynch was disabled. You may be falling into asynch cutting off fuel and engine dies. My idle however was 850 back then. Check log for asynch mode.
80 lbs at 25 lbs FP is a lot of fuel. How did you DETERMINE that need on inj size and FP?
Before I had a VAFPR I had 80's at 20 lbs and my DC fell to minimums and stall save would cause a surge. Not sure if engine died. Also I idle synch as asynch was disabled. You may be falling into asynch cutting off fuel and engine dies. My idle however was 850 back then. Check log for asynch mode.
03-30-2011, 10:53 AM
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Re: Tuning with the EBL
Spark advance is 4º, but my initial is 8º, so I'm making an assumption it's running 12º? I'm not 100% sure there though.
Another thing is I've had to run it open loop since I put the engine in, otherwise DC drops to 0 and the engine stalls (I've already zeroed out the async table). Should using the set screw to open the blades slightly help with this as well?
You need either smaller injectors, or lower fuel pressure. Mine ( 80 lb injectors, 24 PSI fuel ) runs 2% at idle, on the hairy edge of losing control.
At which point I'd expect it to foul and stall, at least go into stall saver, and maybe surge. Still, the DC of the injectors is REAL important here.
So where I'm going with this,...is the IAC running low to keep the idle speed down with an excess of fuel? If your not making 90 on the VE I would consider dropping the fuel pressure slightly. Let us know.
ANY fuel at "zero" air should go rich !
It's the reason my idle SA setting is near 20 degrees less than the spark table for actually running ( rolling the vehicle at "idle" ) at that RPM/MAP.
03-30-2011, 12:50 PM
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Re: Tuning with the EBL
My point in asking the RPM commanded was to determine if IAC is dropping to zero that could mean it cannot achieve that idle RPM which I think is a bit low. It has to set IAC steps to zero. At that point it cannot reduce any further. If the throttle bades are closed too far it will die.
80 lbs at 25 lbs FP is a lot of fuel. How did you DETERMINE that need on inj size and FP?
Before I had a VAFPR I had 80's at 20 lbs and my DC fell to minimums and stall save would cause a surge. Not sure if engine died. Also I idle synch as asynch was disabled. You may be falling into asynch cutting off fuel and engine dies. My idle however was 850 back then. Check log for asynch mode.
That's what I was thinking. I opened them a little quite some time ago when I was trying to get it to idle smoothly, but haven't really messed with them since because it didn't seem to make a huge difference, and it idles almost completely down to the target RPM.
EBL is WYSIWYG if set up correctly, meaning your initial spark really is what your initial spark is ! If that's true, then the WUD should agree with a light. If it doesn't, then something is quite wrong.
Probably not. DC going to zero says you're out of range on the injector.
You need either smaller injectors, or lower fuel pressure. Mine ( 80 lb injectors, 24 PSI fuel ) runs 2% at idle, on the hairy edge of losing control.
...
I'm not sure 13 is all that rich ? Originally, ( GM factory ) mine idled rich enough to asphixiate small children, animals, and some plants, but it idled smooth. After a bit of work, it idles now with some weird BLM, but mostly smooth, so I know it's close to 14.7:1 and that I'm on the edge of the injector range. My IAC is around 5, more or less, at idle. IAC is air, not fuel !!
...
At which point I'd expect it to foul and stall, at least go into stall saver, and maybe surge. Still, the DC of the injectors is REAL important here.
You need either smaller injectors, or lower fuel pressure. Mine ( 80 lb injectors, 24 PSI fuel ) runs 2% at idle, on the hairy edge of losing control.
...
I'm not sure 13 is all that rich ? Originally, ( GM factory ) mine idled rich enough to asphixiate small children, animals, and some plants, but it idled smooth. After a bit of work, it idles now with some weird BLM, but mostly smooth, so I know it's close to 14.7:1 and that I'm on the edge of the injector range. My IAC is around 5, more or less, at idle. IAC is air, not fuel !!
...
At which point I'd expect it to foul and stall, at least go into stall saver, and maybe surge. Still, the DC of the injectors is REAL important here.
I'm suspecting IAC is trying to lower idle because of too much spark advance, based on the confusion quoted above.
ANY fuel at "zero" air should go rich !
It's the reason my idle SA setting is near 20 degrees less than the spark table for actually running ( rolling the vehicle at "idle" ) at that RPM/MAP.
ANY fuel at "zero" air should go rich !
It's the reason my idle SA setting is near 20 degrees less than the spark table for actually running ( rolling the vehicle at "idle" ) at that RPM/MAP.
03-30-2011, 03:37 PM
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Re: Tuning with the EBL
When I originally put everything together the set screw was already uncovered, and I had the blades completely closed, it doesn't really seem to have had any effect either way until lately when it's shown to not drop down to the targeted 500rpm, lowest it's gone lately is 650 or so I believe.
If the blades were really completely closed, you'd have a high IAC count.
The air must come from somewhere !
I see nothing wrong with a 500 or 650 idle.
You say you're set at 500, but it's idling 650. THAT explains a zero IAC count.
Throttle open too far, or a vacuum leak.
In closed loop it just simply has too much fuel available, and when it tries to adjust for 14.7 range it gets ragged and stalls 90% of the time.
That's what I was thinking. I opened them a little quite some time ago when I was trying to get it to idle smoothly, but haven't really messed with them since because it didn't seem to make a huge difference, and it idles almost completely down to the target RPM.
Initially the BIN was set to 0º advance, but I had never put a timing light on it because it seemed to run fine and didn't knock, but I know what you're saying. After ironing out a couple other major things I actually checked and set it accordingly (8º). That's why I'm not 100% sure of what it's set at.
but I'm thinking I'll simply set it to 0 initial since the computer controls the timing and I can modify it as needed.
Mine runs in the same range, 2-3% (pulse width is down around 0.9-1.1mS).
The odd thing is it doesn't always do the surging thing. It often does it more when it's cold, but also when it's warm, kind of a hit-or-miss thing. When it's not surging it sounds like you mention... idle is slightly ragged and not stock-smooth - which doesn't really bother me so long as it's steady
but idle is also closer to stoich, in the 15:1 range.
Part of the reason I'm trying to get a leaner a/f ratio is so I wouldn't have to mess around with this again next year when it's time for emissions testing again.
I've been trying to actually get the IAC to move somewhere other than when the throttle is open, hoping that once I get that to happen it will have a little more control over idle.
I've been doing some more reading/looking at what SA terms are what, and I think I may have it sorted out. It was showing 4º more than what I thought it was supposed to at idle, and I believe I found the culprit, I'll have an update next time I flash the EBL.
If the duty cycle doesn't hit zero, there's still some range.
True, at 1% it's erratic and out of control. At 2% it's on the edge. As long as it stays 2% methinks he's OK. Not dead stock Cadillac smooth, but OK. Much like mine.
Before I bought a vacuum regulator, I'd back off spark to lower RPM, and get a couple IAC counts, keeping the duty cycle 2%.
03-31-2011, 01:53 PM
#1447
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Re: Tuning with the EBL
To quickly answer a couple questions, VE is near 90 in a few spots after doing some learns, I managed to get some IAC action. Apparently there is something that is preventing he blades from completely closing, still have to sort that out... but the IAC is working properly when the throttle is completely closed, and it idles right at 500rpm. I'm not sure when I'd get around to checking with a timing light, and for now I won't be doing anything with the regulator until I can afford some down time on the truck.
03-31-2011, 02:07 PM
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Re: Tuning with the EBL
Ok here are my VE's combined. I reset my AE PW Map and TPS using what Rob suggested in an earlier post. I haven't changed my VE in the areas that are Outside the driving Im doing(ve learns).
The learns are well balanced. Im going to lower my AE PW TPS due to me still having that rich condition. It only happens when Im not at Operating Temp. I am NOT going to touch the AE-MAP.
I am still hitting 100% in VE but it only wants 1 or 2 Higher I may not worry about it.
The learns are well balanced. Im going to lower my AE PW TPS due to me still having that rich condition. It only happens when Im not at Operating Temp. I am NOT going to touch the AE-MAP.
I am still hitting 100% in VE but it only wants 1 or 2 Higher I may not worry about it.
Can someone address this post for me. Looking to see if im on the right track.
Thanks
03-31-2011, 02:15 PM
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Re: Tuning with the EBL
Now we are back to the throttle shaft, check for play & spray w/carb cleaner to determine the extent of wear.
03-31-2011, 03:42 PM
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Re: Tuning with the EBL
I managed to get some IAC action. Apparently there is something that is preventing he blades from completely closing, still have to sort that out... but the IAC is working properly when the throttle is completely closed, and it idles right at 500rpm.
Worn blade shaft ?
I'm not sure when I'd get around to checking with a timing light, and for now I won't be doing anything with the regulator until I can afford some down time on the truck.
Have fun !