First off, I'd like to thank all who have given me input on understanding the 16168625 ecm tables. I have made huge gains on this project going from a stock program which wouldn't even run the new motor to now having a motor that will run with knowledge I've gained from here. I have only worked on idle. I have not yet worked on any other parameters as yet. I want to get idle 100% before I move on. With everything I have programmed I can not seem to get it to idle any smoother than where it's currently at. I know it can be done, I'm just not sure with my knowledge of this ecm where my next change should be.

For example: My 02 mv are high indicating rich but the blm's are all pretty much @ 128. It's idling around 750 rpm but at this RPM, IAC counts vary from 70 - 150 or so... after a while it gets rich then dies.

Any suggestions on what to try next...I'm totally stumped! I have datalog files of it during idle if if would help someone point me in the right direction. I feel I'm really really close but I'm missing something.

 

In idle, there probably wont be any closed loop fueling for a period of time after startup, hence the 128 and rich O2s.

Posting the datalogs wouldnt hurt. Might give some indication of whats going on.

 

That seems to make sense...but what about the high iac counts? I would prefer to reign in the iac counts using the ecm rather than using other methods of dialing it in as in setting the minimum butterfly opening then adjusting the tps.

I will post the data logs if I can figure out how and will I let you know when I do.

 

That seems to make sense, but what about the high IAC counts? How would I go about reining them in? I would prefer to do it thru the ecm rather than the optional method of opening up the butterfly then setting the tps.
I will try and figure out how to post the data logs (there very small... 5 - 10 mins running time or so) if I cant figure out how to post I will try and send them to you if that's all right?

 

Zip the datalogs up, and post the zip file here. Click the 'manage attachements' button, and you will be given the option to select the file from your hard drive.

As far as the IAC counts go, with the PCMs, you really want to do anything to keep the counts down. The routine is much better then whats in the earlier computers, so you dont really have to, and it could result in IAC errors being set if the integrater terms in the PCM keep zeroing out. Trying to control the counts could also cause the PCM to needlessly reset the IAC and loose its learned closed loop idle corrections. Unllike the earlier computers, these actually retain idle corrections even after the engine shuts down.

The high IAC counts could be a result of either a faulty IAC, the PCM trying to prevent a stall, or the tune in the idle routine not matching the specs. of the engine.