ok just finished up a a4 to m6 swap and having the strangest problems wit the way the car is running (yes i am seeing some codes because the it still has the a4 program and the speedo is not hooked up ... but after about 15 mins the car will hunt and search for idle then stall .. then it will run fine for about 15 min again then search for idle randomly ... also when this happedn i can hear the car popping through the exhaust (random) then run fine and start all over again rrrrrr

my question is since the pcm is not seeing the a4 is it going into limp mode? or something else (this car ran perfect before swap )

 

Reprogram to an M6 tune and report back. The PCM is getting no park/neutral feedback with the A4 shifter gone.

 

so would that cause the pcm to flip out randomly?

this is what i am seeing on the scan master (note this has all happen after the a-4 to m6 swap the tranny codes i can understand but the others one just popped up (note i only put about 15 miles on the car since the swap)

16 Distributor ignition system (low resolution pulse)
18 Injector circuit(s)
24 Vehicle Speed Sensor (VSS) circuit
51 EEPROM programming error
81 Transmission 2-3 shift solenoid circuit N/A
82 Transmission 1-2 shift solenoid circuit

 

Its obvious that T56 you installed is a POS.



..... oooooops, wait a minute, that's the one I sold you.

 

The idle speed in the A4 program is a function of whether the trans is in drive or neutral. The absence of the park/neutral switch could cause confusion. The idle speed is also adjusted based on road speed, and without the VSS, that would mean the PCM is not boosting the IAC counts to prvent the engine from stalling when the throttle suddenly closes.

As a minimum, hook up the VSS. Its going to read about 40% of actual speed, but even a bad signal may be better than no signal at all.

 

yes hmm yes that would make sense I just got the pigtails for the trans just have not has the time to wire it in.

 

It's just kind of futile to try to troubleshoot something when all the work is not complete.

 

Yes understand but i was doing some shake down runs to make sure the tranny and everything else was ok

 

The 16 is an OPTI low res this could cause the stalling after 15 mins of engine running. The DTC 18 injector circuit error will shut down the failing injector/circuit may not cause a stall if it's only one injector, but ODB1 does not let you know, if it's on multiple injectors or a complete bank it could be the stall problem. You need to reset codes start it up and scan it after the first stall to see if you can pin it to one DTC. The tranny and VSS codes are obvious, get the correct code loaded and VSS setup per previous posts. This from the book, I have never actually seen a DTC 51.. The 51 is an internal PCM check sum error, defective/bad code load or defective flash memory (EEPROM module), if it comes back after a PCM reset try reloading the PCM code (good time to get the M6 loaded). If it still comes back after that you could need a PCM as internal check sum or EEPROM failures are not field repairable.

 

Thank you for the feedback I will fix all the little things and send the pcm out to byran from pcmforless.com to reflash the pcm for the m-6 set up (he also did the tune for the superchager set up)

will update after all done