Hoping someone can help me out with this one.
My customer has a 1995 camaro (original LT1 car) with an 06 LS7 GM crate engine swapped into it. The only thing done to the engine itself is an intake, set of long tube headers and then unfortunately into that traditional camaro 3" y-pipe and everything is mated to a T56 6-speed tranny. Another shop did all the work to the car including getting it up and running originally. It has the normal drivability issues (stalling, serging, hard starts, etc) and wanted them fixed. I have been tuning these cars exclusively with HPT over the last few years (have done a few C5's and C6's, supercharged and tt) so I figured it would be no big deal. When I went to connect to the computer it would fail at the authentication process and not go any further. I found this strange as it was the first time I had seen this error. I got ahold of HPT and was told that the computer had been locked by someone else and that it would either have to be replaced with a stock computer or unlocked by whoever locked it.
I then started to do some research on the car and where everything came from. I found out that in addition to the aftermarket "plug and play" engine harness they also installed an aftermarket ecu from the same company. I called up the company and was told that it was ordered over two years ago and that no one there would of locked the file. They did tell me to send the ecu back to them and they would then send me a stock ecm untouched for me to work with. I figured all I would have to do is disable the vats and be on my way. A week goes by and the new ecu shows up. I plug it in and sure enough I get the same error message, fails at the authentication process of the read. So of course with the VATS still enabled in this "stock" ecu the car does not fire. I call the company back and he basically has no clue, says that they don't lock the files but at the same time can't tell me what software they use to tune them in the first place. At this point I kind of think they outsource the ecu work and might not know the answers I need. I will leave the name of the company out as It doesn't help solve my problem.
From there I kind of went out on a limb and ordered a brand new ecu from GM for an 06 ZO6 corvette. I have a customer who has an 08 zo6 tt that we did last year so when the ecu came in he brought his car in, had the dealership install the new ecu into his car and flash it with his stock file and os (the dealship can't do bench flashes here for some reason). They then removed the ecu and put his back in. When I got the ecu back from my customer I flashed in a stock file from an 06 zo6, did a full write and the car fired right up but when I went to read the file back out of the computer it came back with that great error saying vin/os missmatch. I then changed the VIN number to match the OS and everything worked as it should.
First thing I noticed though is that the car is not charging, 12.0-12.2 at the ignition. Check into the alternator and the wiring and it turns out that there should be three wires running to the alt in an 06 LS7, two back to the computer and a 12v "alt sense" wire. The two back to the computer were there but the 12v wire was not in the harness, so after running that wire the car charges 14.1 at idle. Next thing I checked was the oil pressure and sure enough that is not pinned into the harness. They have one wire coming out of it to make the gauge in the original cluster work. After talking to a few people I am not convinced this is a problem as a lot of the swap harnesses are laid out in a similar manner and the car is working fine at this point. Remove all the other codes that need to be removed anyway and off to street tuning.
I take the car out on the street for a few hours and get everything in the bottom end of the tune worked out. Car drives really nice and all drivability issues are gone. From there I strapped the car down to the dynojet dyno that we have been using and Finnish tuning the car for wot. Spend about an hour on the dyno with it and things are going pretty good then all of a sudden I start to make a pull and the car goes into limp mode, I lose all throttle control and the car comes down to an idle. The code that concerns me is P0606 pcm internal fault. I cleared the code and the car came back to life so I made another pull and everything was fine again. I finished up on the dyno and the car ended up putting down 466rwhp and 444rwtq, not too bad for an intake and questionable exhaust. At this point I'm happy, the car is happy and the customer will be happy, then came the road test.
It seems that when you are out on the road the car drives great till you really step on the gas. Any sudden wot condition seems to trip this p0606 code and the car goes into limp mode. I clear the code and the car comes back to life. I was able to do one good pull with it out on the street without it setting this code and it really worked good, but obviously that is not good enough.
Things that I have tried are making sure that all traction control is off, that the airflow tables and etc settings have enough head room for sudden TB changes (I think), the etc opening rate is all set to 100% effectively disabling that. I have not seen this problem on any other cars but after reading about the different os's for the E36's and swapping between older and newer os's on other forums, and not knowing exactly how the car was put together and the problems right from the get go I'm starting to scratch my head. At this point I'm not sure if it is something missing from the harness itself, the ecu or something I am missing in the tune. I have also read that different pedal setups can have an effect on the I am hoping that someone here can point me in the right direction as I would love to give this customer his car back but I can't do that till I get it to work right at wot.
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Originally Posted by raven3800t
