I'm at a loss. Please read this link for my engine trouble.

https://www.camaroz28.com/forums/sho...d.php?t=748516

I started working on trans adjustments. Nothing radical, just minor shift timing adjustments to match what I had in the previous tune when the trans shifted fine. I take it out for a test drive and scan using datamaster. Right away I get code 58, high temp, although it is only reading 188 deg f. Also, TCC won't lock but shifting feels fine, and when in 4th gear, SLIP RPM shows -4096. So, I again compare the tune that the trans worked fine with and the current tune, everything is identical. So, I reprogram using the last $EE bin when the trans was fine. Take it for a drive and everything is back to normal. No DTC 58, TCC locks and slip rpms under 10 when holding speed. But with this .bin the backfire and hesitation is back. I'm almost thinking a PCM problem but with different .bin's the problems change. Any thoughts?

 

Looked at your other post (link) The $EEB definitions were for early '94 PCM level "B" software. Later in '94 PCM software revisions "C" and "E" replaced "B" . I would insure you at are software level "E" and then use TC definitions file $EE for any updates. Whenever you load level $EE tune the software is uploaded to the 'E' level. And if you load a $EEB then it's backed back to revision "B" . Also if you are using F-body tune with $EE definitions the PCM should not be looking for CCM communications. Are you now running '94 $EE F-body setup code with a '94 4L60-e transmission when it messes up ?

 

Let me try and clarify what I have done. The PCM is a service #16181333. When I first read the PCM I had to use the $EEB def but at the time could not reprogram using a modified Vette tune because I lacked the CCM interface. So, when I had purchased tunercat he also sent a F-body A4 bin that I modified for my application, it required the $EE def file to read, so when I programmed the PCM I left it set to $EE. Everything seemed to work except for the hesitation and intake backfire but I lived with it for some time cause I didn't have a lot of time to play with the PCM. Recently I discovered that the updated tunercat appeared to have an option to make the Vette tune work without the CCM so I tried it. To my surprise I was able to modify my original Vette tune and reprogram the PCM with the $EEB file. Low and behold my hesitation and back fire went away. However I ended up with the tranny issues I listed above. Other than the TCC not locking up the trans seemed to shift fine and I didn't feel any slippage. So, I then took that Fbody A4 file, only deleted the emissions stuff and reprogrammed the PCM. Engine went back to crappy but the trans works just fine. From what I have read, the def files ($EE or $EEB) only allow you to read and modify everything but shouldn't matter when you reprogram.

 

Any possibility of getting a DataMaster EE log of the backfiring, hesitation conditions when using the F-Body A4 tune, as it seems that's the tune that works with the transmission. You can e-mail me a copy of the log (.uni) and the tune (.bin) maybe I can see something out of whack causing the engine problems. If you don't have it already TTS DatamasterEE is a free download for 20 logs. ASLO can you verify the transmission is a '94 4L60E not '95 or above, there is a software/hardware compatibility difference (TCC PWM Solenoid)

 

I emailed you those files. And yes, trans is a 94, only has the 12 pin connector.

Brian

 

Took a quick look, the data trace has a weird problem. You never get out of BLM cells 16, 17 18. All your non non TPS=0% running is in BLM cell 18 you never use cells 0-15. Not sure what would cause that the BLM MAP and RPM boundaries tables are at stock settings, so they are not the cause. I then looked at your .bin file and noticed your PCM is loaded for a Y-body calibration (Tools tab, then click Vehicle Information) , but your speedometer setup page (Tools-Speed Calibration) has F or B -body radial button selected. You don't happen to have a F-body load somewhere. If not I may have a stock '94 A4 Z28 file around I can send you. Would be interesting to see if a different calibration load makes a difference. I will do some more looking later on.

 

Hmm. Something has gone astray. I also just looked at that .bin I sent you and it cannot be the Vette tune. That vin is the original from when I got the PCM and should require the $EEB defile and it dosen't. And like I said, until just recently I wasn't able to use that file becasue I couldn't disable the "Data Stream enable" option to keep the car running. Up until just a couple of weeks ago I have been usng a 94 Fbody A4 file which should be the one I sent you. In fact, looking through my last several revisions they now all show the Y body vin. Very odd.

Brian

 

If your PCM has the vette VIN in it and you write any tune to it, then reread the tune, it will show the vette VIN.

Separate function in tunercat to change the VIN in the PCM.

 

Ok, as luck would have it, I forgot I had picked up a B-body PCM from a wrecking yard a couple of years ago so I installed it today, put a 94 Y body tune on it and all seems fine at this point. No hesitation or backfire and trans appears to be shifting fine with no error codes. Only problem I see now is I never leave cell 16,17,18. Only changes made to this file were deleteing emissions, gear change and fan temp. And it does go closed loop. Any thoughts?

Brian

 

Just to clarify:

Y PCM + Y $EEb tune = shifts bad
B/F PCM + same Y tune = shifts fine

Y PCM + F $EE tune = shifts fine, engine stumble


Have I got that right?


I would start a new thread on the problem of staying in cells 16-18, with a link back to this one.

 

I will post a new thread for the cell problem.

 

Ok, all seems good now. Current setup is B-body PCM, 94 Y body tune. Very little hesitation (tuning maybe) off idle but no back fire off idle or when going WOT. So my thoughts are this:

My orignal Y-body PCM ($EEB) was from a M6 car and I tried to make the Auto work but for what ever reason it wasn't.

Orignal Y-body PCM with an F-body ($EE) tune didn't work but maybe the tune had a error in the backround that casued my engine woes. This makes sense since when I programmed the B-body PCM with the F-body tune my hesitation and backfire returned. I even went so far as copying all of the Y-body tables, minus the trans stuff, to the F-body file, and the problem was still there.

So, after searching I found a 94 Y-body tune A4 ($EE) file on the monodax forum that appears to be working now.

Hope this helps someone else in the future. Now at least I can enjoy the car.

Thanks
Brian