Okay its a long story so I will try to make it short and concise. I have been reading A LOT on here to try and get myself up to speed.
2010 Cobalt SS LNF that is completely stock other than a hotside charge pipe to replace the faulty stock one.
I bought the car used from a Ford dealer. Found out later that it had all the sensors and stickers that would lead me to believe it was GMS1
Car had horrible long term fuel trims (15-20%) that fluctuated a lot and would run like crap if I installed a K&N SRI. Boost would only get to 17psi.
I found a bunch of boost leaks and fixed all of them. Tried replacing a bunch of other parts as well and nothing ever solved the problem. I even had the turbo replaced under warranty since the compressor wheel had started to bash the housing.
Bought HP Tuners from another user on Cobaltss.net to try and log/read to see if something was up tune-wise. Log did not look weird other than the aforementioned high LTFTs. Here is the original log:
http://www.mediafire.com/download/8g...redworklog.hpl (not that great as I was still learning how to configure my scanner)
Read the ECU and compared it to a GMS1 file that I got from the user that I bought the software from. They did not match. MAF correction/base tables, TM tables, injector pulse length, and other not so in depth (no timing or cam changes that I saw) were all different. I am assuming that the original user had an intake and tuned for it then removed the intake (or other parts) and then traded the car in.
GMS1 file from seller: http://www.mediafire.com/download/ca...psp1c/GMS1.hpt
My car's original tune file: http://www.mediafire.com/download/qf..._9_15_2013.hpt
I want to return the car to GMS1 so I can try to retain my powertrain warranty if something goes wrong.
I tried to flash entire (I was told to do that on the cobalt forums) the file I received from the seller and instead of being required to license it I was given an error message that the calibrations conflicted. I am assuming it is because he had it previously licensed for his car. I had already licensed my cars original file.
I read on here that I just need to open my original car file and then the GMS1 file as a compare and then use the differences log to copy over all the changes and then save as a new file. That is what I did. Here is the file:
http://www.mediafire.com/download/90..._9_16_2013.hpt
I then flashed the car with write configuration and logged it. Other than a few odd jerk/coughs at WOT in second for the first few tries the car then ran great. Was real smooth, boost was almost to 21psi and the LTFT was back to zero. I logged the car again (of course after the hicups which I am pissed I didn't catch).
Log file is here: http://www.mediafire.com/download/tf...redGMS1log.hpl
NOW the BIG QUESTIONS that I have been leading up to is: Did I do this correctly? Do I need to get a GMS1 file from a different origin and then write entire? Should I trust that the car was tuned by the previous owner off of a GMS1 base tune?
This is my first time ever tuning/flashing a car and is my daily driver so I just want to make sure I did things correctly and will not damage my vehicle.
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