jimmas

I just had my engine rebuilt. The heads and plenum are ported, Edelbrok intake and runners, Hooker 2151 headers, 24# injectors and a comp cam. The cam specs are here.....http://www.compcams.com/Technical/Se...umber=08-501-8

I've been playing around with my VE tables and have had quite a bit of success. My only problem is that my idle is very rich. I've read on here that I should turn off the CCP and I thought I did. I use Tunerpro RT to tune and was told to set "Canister Purge Fore BLM Idle Cell Min/Max. Duty Cycle" to 0. I did that but during my scans with Datamaster my CCP DC is all over the place. How exactly do you turn it off then? I've also been reading that I might need to adjust my 02 voltage in order to correct my rich idle. How do I do that? I couldnt find anything really clear on here. Any other tips to correct a rich idle? It idles in cell 5 at open loop, but in closed loop it idles in cell 4 if that matters. Thanks!

jimmas

In Datamaster I got my idle STerm-C Counts to 128, but my LTerm-C Counts stay at 108 all the time. It is still burning very rich (Smoking and a strong gas smell). Any ideas how to correct this? My fuel pressure is at about 40lbs.

Gary Anderson

iTrader: (2)

LTerm-C Counts is the BLM. That is the one you need to get @ 128. Need to lower the VE numbers in the area where the motor idles. (MAP vs RPM)

jimmas

Thats what I figured. I've been lowering the numbers in the VE table like crazy but its sitting at 108 all the time. Do I just keep going lower? I'm taking the blm of 108/128 which equals .844. I'm then multiplying that by the number in the VE table. Is that correct? The weird thing is that if I run a log through VEMaster is increases my VE table.

jimmas

I lowered the values in the VE table even more and now the car barely idled. It was smoking even more and had a very rich gas smell.

Gary Anderson

iTrader: (2)

Then I would try and raise the VE values just to see what would happen. Where did you get the XDF file you are using? Maybe it has the formulas wrong for the VE table? I normally use Tunercat and the latest revision of the definition file (same as the XDF for Tunerpro) I got from TC has some errors in it that had me chasing my tail for a few days.

jimmas

I thought about raising the values in the VE tables actually but wasnt sure if that would help. The only tunercat file I can find is the demo with the ECM42. I cant load a 8d file in it.

gta324

Whats your timing?

Can you post a scan?

jimmas

The timing is set to 6 degrees. I have a datamaster scan if you want to look at it. Thanks for the help!
http://www.mts.net/~jimmers/Run 13.uni

gta324

The stock bin and the modified ?


The BPW seems to be in the correct ballpark......

jimmas

Thanks for the help!!
This is the stock bin.
http://www.mts.net/~jimmers/stock.bin
This is my modified bin.
http://www.mts.net/~jimmers/modified.bin

jimmas

I forgot to ask, do my 02 voltage readings seem ok? I'm not sure if I should replace my 02 sensor. The car was burning coolant for about a year, so I dont know if the sensor went bad because of that. I'd hate to throw a new sensor in and have all this rich exhaust mess it up.

gta324

1. If you think your O2 is bad replace it, not that much money! you can tune and tune for hours then start over again if the sensor is bad.....

2. Your Ve doesnt look good.

3. Why have you changed Min/max BLM?

4. My suggestion is replace O2 start with a new (stock) bin and just change inj size. Maybe raise the SA at idle areas some, (dont know how its running at idle)

/N.

mike1986fyrbird

Replace that 02 as already said. You arnt getting many crosscounts at idle.

Those VE settings in your bin at WAYY too low at 15%VE. They should be fairly close to stock with that cam.

Tables to modifiy;

Spark Advance Closed Throttle vs. RPM
Try changing the 0, 400, and 800rpm values from 20* to 24*

Your timing is all over the place at idle do to rpm corrections.
It is ranging from 7* to 22* at idle.

Try zeroing out or greatly lowering the values in these two tables;
Idle Spark Retard vs. RPM Error
Idle Spark Advance vs. RPM Error

jimmas

I was told to change the Min and max BLM to 128 then tune. I guess they were wrong. I'll pick up a new 02 sensor tonight. Thanks for the help!
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I figured the VE tables where to low. I was told to keep lowering them until it doesnt run as rich. Thanks for the help, Ill give those tables a try and scan the car.

jimmas

Well I made all the changes you guys said but its still very rich. Here is a link to the lastest scan. Once the car entered closed loop it started to surge a bit and run very unstable. I'm not sure if thats from changing all the spark stuff or what.
The scan
http://www.mts.net/~jimmers/spark changes.uni

Here is the bin I used.
http://www.mts.net/~jimmers/spark changes.bin

Also should I lower my fuel pressure? It seems as the car gets hotter it burns richer. Would running this rich have anything to do with the engine physically? Thanks again for the help!

jimmas

Would raising the injector constant help with leaning it out?

gta324

What fuel pressure do you have?

When you do changes in VE look at the graph and make sure it is smooth. RIght now you have a deep valley and thats not good. If the engine takes a bump to higher/lower rpm/map the VE is much higher and the BPW will change alot and it can make an idle rough/rich.

There is one more idle SA table you can put to 0. When you have tuned SA and VE at idle and you can activate these tabels again to get a more stable idle, sometimes it get worse with these activated sometimes better.........

/N.

jimmas

So I put both SA tables to 0, now I should tune my VE tables? How much lower do you think the VE tables should be at my idle RPM/MAP?

jimmas

I changed the other table to 0 and it seems its burning more rich. I changed the Ve tables also but no change. The BLMs stay at 108.

EdgesZ28

Verify that your MAP sensor hose is connected or not split.

Ed

jimmas

I checked it many times and its fine.

Bethann

Jimmas/Jimmer(corvette forum),

Lets do a sanity check here:

Ok, so you tried to disable the "idle cell 4" and it didn't work (...some other post). Is that correct? Since your cam change, the car should be idling at a higher MAP value than stock (due to less vacuum). Your computer is still trying to hold the idle in cell 4. Your editing software is different than tunercat so you may not have access to this variable (does anyone know for sure?). Are you adjusting the fuel in cell 4?

This business of changing the limits of the BLM to 127/128 (as opposed to 108/160) is valid. It just turns the BLM correction off so you're not chasing your tail during the tuning process. This is a feedback control loop (in closed loop anyway). It's confusing in a "speed density" system because little things like temperature and pressure variation have a big impact on the data you collect. So if you log data in morning (when it's 75 degrees air temp) or in the evening (when it's 95 degrees air temp) you'll get different results.

Tuning in closed loop (for a speed density system) is somewhat like trying to hit a moving target. It can be done but you need to know what you're doing. When I got started and had similar problems, Grumpy (now a legend), told me to quit screwing around with closed loop tuning, buy a WBO2 and run open loop. I finally took his advise and tuning became a breeze. Of course I didn't care about gas mileage and I'm not running at 14.7 AFR. The engine idles at 13.5-14.5 (depending on outside air temperature) and runs 12.5-13.5 pretty much everywhere else. That's the way I set it up.

...it's painful to see you struggle.

gta324

What fuel pressure do you have?
do you have AIR connected?

Tuning closed loop without WB is "impossible" That cam isnt so big so It should be "ok" to tune in closed loop, a WB would help.

Idle map is around 45kPa isnt so bad, my previous cam idle at 70kPa at 850 rpm, and It idled "OK" in closed loop, now I tune in Open loop....another story..

Where did you get the "stock" bin from, maybe its "hacked" have you tried Super AUJP V3?

jimmas

The fuel pressure is currently at 40psi and I removed the AIR a few years ago. I got the stock bin from Moates sites. I wasnt sure if I could use the AUJP bin, I guess Ill give it a try. Thanks!
----------


I was told that by setting the CCP min/max values to 0 it would be disabled. The car still idles in cell 4 though. I believe im editing the fuel in cell 4. I edit the VE table in which KPA and RPM the car is idling at. Is this not correct? Thanks for the help!

jimmas

I tried the S_AUJP_CCP_V3.bin but it didnt help. When the car first starts theres a huge cloud of rich smoke, and continues to smoke as it idles. I'm completely lost. Whatever I change doesnt seem to help.

mike1986fyrbird

Did you change that 02 sensor?

gta324

Disable AIR in Prom
Injectors to 24
Force BLM at idle remove (adress 522 set to 0)
Lower the whole VE by 108/128 and see how it respons.

Injectors any chance they are leaking?

jimmas

I tried a new bin last night with those settings and it didn't make a difference at all. The car runs rich in open loop and closed loop.

How do force BLMs at idle in Tunerpro? The injectors are brand new so I doubt they are leaking, but they could be. I'll check that out.

BMmonteSS

Stupid question, but what is your fuel pressure with the vaccume line hooked up? Kinda sounds like you are tuning around a steady state fuel pressure.

jimmas

I did replace the 02 sensor.
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It reads 40psi.

jimmas

I talked to a mechanic at a local tuner shop today and was told that the software im using wont work with my car. He said the tuner there contacted the company awhile back and they said it has problems reading the load tables??? He said no matter what I change it won't effect the car. I 'm not sure exactly what program he was talking about because I didnt speak directly with the tuner, but has anyone heard anything along these lines? I use Datamaster and TunerPro.

Gary Anderson

iTrader: (2)

Do you actually burn chips or use the RT deal to make your changes?

jimmas

I burn the chips with the Moates Burn 1 programmer.

Gary Anderson

iTrader: (2)

If you are making all these changes and nothing helps it would seem to me that the engine is getting fuel from somewhere besides where it is supposed to. Is there any fuel in the vacuum line to the FPR? Have you disconnected the vacuum line and run it like that?

Maybe just for grins zero out the VE table in the idle MAP & RPM areas and see if the thing will even run like that. If it does run with 0 injector BPW it has to be getting fuel from a leak somewhere.

RBob

iTrader: (1)

I'm in agreement, something funny is going on. Even thought for a moment that it may be in limp mode, but data logging works.

jimmas, if the chip you are using is larger then a '256, is is being offset burned or stacked before burning?

RBob.

jimmas

The bin that I burn to the chip is only 32kb.
----------
I have run the car with the vacuum line disconnected and its still rich. Tonight I will zero out my VE tables at idle and see how it runs. I wont hurt the car doing that?

jimmas

I set the VE tables to 0 in my idle RPM and MAP areas and the car still idled and ran very rich. I scanned it during this time and it ran exactly the same as before.

Am I doing somthing wrong?? Its almost like my ECM isnt reading my chip. Is there somthing that isnt compatible?

1tpi

Was it running in closed loop, if it was in open loop did you change
those tables

jimmas

It ran in open loop for a bit then went to closed loop just like normal.

RBob

iTrader: (1)

OK, but what size is the chip? If the chip is larger then the BIN, which is common today, it is possible that you are burning the wrong section of the chip. That is why nothing is changing.

Note that the BIN's and chips are rated in different size units. In 'size' units a BIN is 1/8th the size of the proper chip. Bytes vs. bits.

32 kB BIN is a '256kb chip. Such as the 27C256 used in the '7730 w/$8D.

RBob.

jimmas

Well everyone it looks like I finally got the BLM's to level out at idle. I figured I'd try another bin (ARFP) for the heck of it, made the changes you guys said and it worked!
Heres the datamaster scan. I got it to run lean for a bit, then made some changes and it leveled out. If you scroll to the end of the file it is my last scan with the VE table changes.
Is there anything else I sould change for my idle, or does everything else seem ok?
I want to thank everyone for their help with this.
http://www.mts.net/~jimmers/finally.bin

jimmas

I'm using the 27SF12 chips with the correct offsets that are on the moates.net site.

camarokid144

i know this is a little off the subject but can someone tell me how to start a thread now

jimmas

Click the "new thread" button at the top of any forum.

EdgesZ28

You probably already thought of this; but considering how rich it had been running recently, I would put a new set of plugs in it before going too far with your tuning.

Best of luck, Ed

jimmas

Ya that already crossed my mind. I took a few plugs out and they actually didnt look that bad. Thanks for the tip though!

gta324

Good to hear, happy tuning.

jimmas

Thanks! I'm sure I will have more questions, but atleast I know i'm on the right track. Thanks again for the help!