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I have been having an issue over the last year with a "hesitation/stumble" in the ~3000 rpm +/- 300 say range when i am just on light throttle cruising speed.
I have had good luck with EBL in my other projects and generally in this project as well, but I haven't been able to get rid of this... Doesn't seem like i am in AE as this is pretty much a constant type throttle and while I have altered those tables it didn't seem to make a difference. Seems like when the problem develops it is when i am getting a leaner operation in closed loop in these areas compared to the area right before / right after
I noticed that this only happens when the engine is warmed up and today I forced it to stay in open loop and have no issues at all, although granted my VE table is a little rich all the way around
Also interestingly I started out this project with a Holley HP EFI as I was thinking about using that platform for all my swaps, but Holley introduced an error in their software for these types of ignition setups and I got tired of waiting for them to fix it (which they still haven't) so last July 4 weekend I tore it all out and put the EBL P4 in and had it running better in 2 days than the Holley ever ran.
Other than this hesitation it runs great, and in open loop it runs completely super but there must be something i am over looking as no reason this mild engine combo can't run normal closed loop
The file attached is my bin (to force open loop all i did was raise the ECT enable to 140). The two datalogs are one in closed loop (PROM ID 00130) with some markers where i can feel the hesitation and then an open loop datalog (PROM ID 00131) today (no markers and nothing to mark in terms of any problems, but i did a lot of reference running in the 3000 rpm point)
Thanks for any advice
just out of curiosity, did you get this sorted out?
So every time I do a VE learn, I'm doing it via my WBO2 and only the top right of the tables will adjust. I noticed when it will learn the cell highlight is green. Everywhere else the cell highlight turns orange and won't adjust. I have the WB selected for VE learns in the preferences screen on the general setup and the min CTS set to 125 deg F and the max CTS set to 220 deg F with a smoothing factor of 4. In the ADC channels I have the AEM WBO2 selected on Channel 0 where the WB button is pressed. I have the Closed Loop Enable set to 150 deg C so it stays in open loop the whole time but I notice that it is still going into closed loop and when any PE or AE is active it won't learn. I had the tune pretty dead on doing manual adjustments and data logging but then I bumped my AFRP up another 5psi because my Duty Cycle % on the injectors was getting over 90% at the top of WOT and I wanted to give myself more wiggle room since it needed a little more fuel on the 95 and 100 load columns.
What else do I need to change to get the VE learns to adjust properly on the rest of the table?
Hello everyone, been a long time since I was here. I recently resurrected my old girl. Lots of work but in short I'm running the EBL flash setup on a TPI 355 with a 5 speed. The only stock parts left in the engine are the throttle body and the plenum that's ported a bit. I'm looking at my datalog and to me (not a tuner by any means) it looks pretty good. The DC is around 70 with TPS at 90. I assume that means the injectors are matched pretty well? or should I use more fuel? The BLM (short term?) stays at 128 for the most part which I thought was strange. I want to start dialing in the timing but I'm not sure I should yet. Any help is appreciated.
So ended up doing the whole bin all over again because I found that somehow ai had swapped bins to the pretty much stock 1006 file..I've now calculated the fuel tables BPCvs VAC, BPC vs Boost, Multiplied the AE Map PW table and TPS table by .856 as described in the Intro to tuning page part 2 for 50 psi fuel and 24lb injectors. She idles steady cold, and overall runs pretty good. Only issue is at around a constant 1500 rpm it has a slight stumble and the tach will actually bounce around a little bit in sync with the driveability issue. Also will surge a bit when coming off throttle. I've added IAc steps, bumped TCC lock to 100mph (it's a 5 speed) pushed closed loop to 100C and set EGR SA to 0.0 degrees (EGR is removed) and set the DFCO to 100C.Now on my 5th VE learn. Any help is appreciated Thanks
Make sure that the TCC option flag is cleared. This way none of the TCC logic is run. The N/V ratio and reverse lockout is instead.
Set the hiway lean cruise CTS enable high to disable it.
RBob.
Hi Rob, thanks for the reply. I had already unchecked the TCC and set the HWY to 100mph but I set the HWY min coolant to 100C as well. I just went for a drive after changing "fan on bump steps to 5 no change. Ill take her for a run tomorrow with the coolant temp bumped up tomorrow. I switched bins back to 1006 today just to see if it extinguished that issue and it did. Thinking I may have the fuel tables wrong. I calculated assuming the 1006 bin had 22lb injectors.
Hi Rob, just ran it, didn't change at all. When she's warmed up coming to a stop with the clutch disengaged it surges pretty bad for a few then she corrects herself. The o2 wave is max rich then lean, seems like she's trying to correct fuel. I've read about smoothing out the low speed VE around this area. Should I give this a go or try something else? I don't know if it's helpful but here's the specs on the car: TPI 355, SLP runners, stock plenum matched, 22lb injectors AFR Eliminator heads 180cc with Scorpion 1/6 rockers, Comp cam 08-302-8, gross lift of 0.48 for both intake and exhaust. Duration is210 intake and 220 exhaust, lobe seperation of 112..and a stock throttle body.
Looks like coming to a stop she leans out to much, O2 goes to 0V then spikes adding fuel to compensate and just gets into a loop. It does smooth out after a 4 or 5 surges.
On a warm engine with no other loads, adjust the idle stop screw to get 20 - 25 IAC steps. The RPM is dipping too low and triggering the stall saver. This is what causes O2 to also spike up (rich).
It looks like the engine settles nicely to a 750 RPM idle speed.
May want to add to the VE table in the area where the RPM dropped like a rock. It would be better to post the graph area and the same area of the analysis screen shots.
So I set the TB screw so that she was around 20-25 steps and set the lean cruise at 200c. Still has the surge comeing off throttle, no worse no better, and the "blip" in rpm also is still there, only seems to happen after being driven for at least 10 min. Here's a couple shots of the surge in the driveway.
I honestly don't understand what you mean by give it more ve where the rpm dropped like a rock. You mean where the kpa and rpm meet on the graph? 48kpa and 587 rpm? Sorry, I don't deal with this stuff in the dealership.
I also have the EGR blocked off, the air pump and canister removed.. maybe there are some flags I need to set/unset? I unchecked the EGR but wasn't sure what the egrNC was for so left it.
I’m sure this will be elaborated on but look at you ve dip add fuel to see if fueling helps stabilize surge.
no / nc is just the solenoid state max egr vs coolant temp to disable operation.
Last edited by Tuned Performance; 08-20-2022 at 10:11 PM.
Been on this a better part of the day, Cold seems fine. Got her to settle around the 20-25 step mark with IAC and set the rpm to 750 rather than 825 in the bin. Started doing the same surging when hot, added 5 steps to fan on bump, no change. Messed with VE several times several road tests, no changes. I really don't know what else to do. Seems to run fine on the stock 1006 bin but I think I'm leaving a good amount of power on the table at that point. Here's the VE table after screwing with it, looks like a mess to me but what do I know.
Been on this a better part of the day, Cold seems fine. Got her to settle around the 20-25 step mark with IAC and set the rpm to 750 rather than 825 in the bin. Started doing the same surging when hot, added 5 steps to fan on bump, no change. Messed with VE several times several road tests, no changes. I really don't know what else to do. Seems to run fine on the stock 1006 bin but I think I'm leaving a good amount of power on the table at that point. Here's the VE table after screwing with it, looks like a mess to me but what do I know.
If it's forced to stay in open loop, does it still surge?
Yes I appreciate that. I don't rule out anything but when I flash in the 1006 bin that came with ebl, car runs perfect hot or cold. If there was a vac leak I would imagine it would be present all the time. The only real chages made from that bin to mine is the 24lb injector calculations, Anything else I've done is to try and correct this BS.
I'm going to run this bin for a while, do some VE learns see what happens. I would think even though it fueled for 22lb injectors she will be adapting for more and more fuel.
Yes I appreciate that. I don't rule out anything but when I flash in the 1006 bin that came with ebl, car runs perfect hot or cold. If there was a vac leak I would imagine it would be present all the time. The only real chages made from that bin to mine is the 24lb injector calculations, Anything else I've done is to try and correct this BS.
wait, I'm confused between me probably misreading previous posts and this one. Which injectors are you using? 24 or 22 and then which ones? Delphi, holley, bosch 3s? Did you change the injector voltage offsets and the lb per hour?
I think I’ve done everything. I followed the @intro to tuning “ there was the bpc vs boost and bpc vs vac . Then the other calculation based on the previous injector size. Forgive me I’m on the phone and am doing bedtime with my little one.
This is what I was talking about …The best way to compensate for a change in injector flow is to use the ratio of the old injector flow divided by the injector new flow rate. Using that ratio compensate the two AE PW tables (MAP & TPS). As an example, say that the 61 #/hr injectors are replaced with 80.5 #/hr injectors at 18 psi. The new flow rate is then 94.7 #/hr.Creating the ratio:
61 / 94.7 = 0.64
Go into your calibration editor and open the two AE PW tables. Multiply each entry by 0.64 (toolbox!). Save tables, save calibration (BIN). Done
wait, I'm confused between me probably misreading previous posts and this one. Which injectors are you using? 24 or 22 and then which ones? Delphi, holley, bosch 3s? Did you change the injector voltage offsets and the lb per hour?
Hope I'm not out of line but, could you elaborate on this? What tables aam I looking for exactly and how do I calculate this?
Hope I'm not out of line but, could you elaborate on this? What tables aam I looking for exactly and how do I calculate this?
not out of line at all. Injector voltage offsets. I'd have to dig or open the laptop and tuner pro for the exact table name. Injectors usually have different offsets. The manufacturer of the injector should supply it. Sorry if my example is difficult to read. Find the part number on those injectors. Maybe it's leading you down a bad trail from the 1006 bin.
not out of line at all. Injector voltage offsets. I'd have to dig or open the laptop and tuner pro for the exact table name. Injectors usually have different offsets. The manufacturer of the injector should supply it. Sorry if my example is difficult to read. Find the part number on those injectors. Maybe it's leading you down a bad trail from the 1006 bin.
Well COVID finally caught up with me last week, so I had a little time to look at the car. I figured out those injector offsets. It's rated a little differently and at a slightly different voltage but ai plugged them in best I could and just moved the decimal. I also found one bolt had backed out of a runner, not sure if it was causing leak but either way the surge is probably 90% gone. I then pasted the origninal blank VE table back into the bin and ran some Ve learns. Seems she is really adding VE right around the spot where the coasting shudder or "blip" takes place. Looks like it's going lean on the diag screen, possible intermittent misfire. Just for good measure replaced cap and rotor as I've had a ton go bad in this car just from sitting in the garage in New England,.. (not this year though) While swapping caps noticed 1 wire doesn't "click" onto cap and has some light rust residue where all other connections look perfect. Road tested, exactly the same issue.Started checking wire proximity to the headers, some are pretty close, no signs of burning. Isolated wires as good as possible just for testing puposes, ran like a total bag of **** under load, backfiring horribly. Suspected I swapped wires but everything looks perfect, Seems to drive perfect when light throttle, even snapping out of gear. Think the wires got cooked, been on the car since 2005. when I was learning VE after setting the offsets car really seem to run perfectly, other than the little "blip" Wires should be here this week so hopefully this will close the case and we can move on to some timing adjustments. Thanks for that info,
It should work. I used an innovate for years until it died. I recommend one with a gauge so you can monitor without your pc attached. I use this one https://www.amazon.com/s?k=AEM+30-03...f=nb_sb_noss_1 because it has a shallow gauge the worked with limited space behind my dash.
so after that day, she still had that slight stumble on light throttle, cruising speeds. I decided to replace the cap and rotor, drove it and was way worse, barely drivable. ordered some new wires from Summit, got a set of 8, no coil wire?? Removed the old wires and sure enough, found one white and cracked burnt by a header. Replaced the ones I had and no change, couldn't believe it. Summit is sending the coil wire but i couldn't wait and went to the parts store and bought a set. installed the coil wire and sure enough, huge change, idles perfect no surge but still has the damn stumble at light throttle cruising speeds!! I also flashed in the stock 1006 bin and it's a little more mild but still has the stumble. At this point I'm thinking dizzy or spark module. The fuel pressure is set to 50, anyone ever have issues with the pressure too high? causing injectors to drip? I'm at my wit's end here. Any help is appreciated.
I had already disabled the lean cruise in the beginning but I finally figured it out. It was a combination of everything. The wires were def an issue but when I moved them got way worse, summit didn't send the coil wire which was most of the problem, replaced it with a cheap one from the parts store, mostly gone. replaced the ignition module and everything is perfect, idle needle looks like it's painted on, no surging, smooth throttle, can drive at 1k in 5th gear with no problems. Did my first VE learn drive today and we'll do some more before I start messing with timing. Now it's time to dial her in!
I just drove on the 2nd VE learn and i have to say she drives just amazing. Shifting up and down the gears is just better than i can ever remember. Any insight on tuning as far as fuel and advance? she's set to 50 psi right now and the whole tune is of course set around that number. If I start dropping pressure to see if she likes it does that mean I have to re write all those tables just to see if its a step in the right direction? Also, are we talking about tiny gains for the race track or can I expect gains I'll feel in the seat? I'm not chasing quarter mile times but I want 100% of what she has to offer. That being said I dont want to spend the weekend gaining 3 hp to the rear wheels. Sorry for the noob questions.
So she idles a bit rough and runs pretty rich, shows 128/128 but starts maybe 9 AFR then slowly climbs until, bingo 14:7 and seems to clean up the smog instantly. I did check the open loop idle back on. Is this normal With the .480 lift cam and 1:6 rockers?
she seems to run great. Upon initial accel almost feels like a dead pedal until about 3k then starts to go. I'm going to start messing with fuel pressure. Any ideas or setttings I'm missing? Something under AE I can try? "IAC opening fuel"? what is that for?
she seems to run great. Upon initial accel almost feels like a dead pedal until about 3k then starts to go. I'm going to start messing with fuel pressure. Any ideas or setttings I'm missing? Something under AE I can try? "IAC opening fuel"? what is that for?
is this wot ir heavy accel only? What's the afr in such state? Add fuel if it seems to need it. Any spatk knock in those areas? Add or subtract timing as it deems. Don't make huge changes, just make judgments based on what it's doing. You can always go back to what it was or change a little more till it feels right.
mostly notice when hard accel in a high gear, as rpm increases seems to pickup. The O2 seems to always be close to 1 V cruising, when i hit it she is almost always around 9 afr. After cruising a bit gets back to 14/7 and the BLM and INT GET TO 128 and stay as long as I don't stab it. Was going to drop some fuel pressure tonight, no signs of knocking anywhere.
So thanks again for answering me. I dropped the fuel pressure to 45 from 48ish. Def seems to like that. stays right around 14.7 and 128 when I can glance over at the laptop. I may try for 43-44 and then change the tables around the fuel pressure. Here's a dumb question, how do i play with timing? The dist is set to 6 as well as the ebl scalar. Do I just move it the old fashioned way little at a time? or with the SA table? Thanks again, I appreciate everything.
So thanks again for answering me. I dropped the fuel pressure to 45 from 48ish. Def seems to like that. stays right around 14.7 and 128 when I can glance over at the laptop. I may try for 43-44 and then change the tables around the fuel pressure. Here's a dumb question, how do i play with timing? The dist is set to 6 as well as the ebl scalar. Do I just move it the old fashioned way little at a time? or with the SA table? Thanks again, I appreciate everything.
use the sa table. That way you can add spark where it wants it and keep it down where it doesn't need it. Like peak torque tends to like a little less timing.
So I applied -1 offset to the SA from 2000 to 3200(peak torque?) up to 80 kpa. Definitely seemed to like it but it could be in my head. Is this the way I should be going about it? Keep dropping a degree and see how she feels, focusing on this area? Then when I feel loss of power bump back up where I was last? Then pretty much do the same in the other direction going up the rpm range to around 5k? Don't think the tpi has much after that.
02-16-2022, 02:55 PM
