2015 Corvettte M7 LT1 to LT4 upgrade- Runs Rough

[jcdives]

My car has been running very rough and when I try to accelerate the car hesitates, backfires and begins to shake. Car was running fine before I replaced the battery and bad starter. The car's info:

660 whp
Tune by Redline Motorsports
LT4 supercharger
Stage 3 cam
Methanol injection
Long tube headers
Z06 HPFP

I always use Chevron 93 octane techron fuel. The car has 20K miles. I have atached a my VCM Scanner log file and tune file. Any advice is appreciated.

Thanks!
Joe
[email protected]

[TheMechanic]

Fix your P2534 first. Then retest

[jcdives]

Ran a cylinder balance test and cylinders 2,4 and 6 didn't affect the A/F mixture and my Long Term Fuel Trims were at -16 and -20 which means the ECU was compensating for a lean condition. This issue started when I changed he battery and starter, so I believe it's an electrical issue which propably means the spark plugs arent firing.

Could that mean the coils are bad at those specific cylinders? Haven't checked that yet. Not sure if my xtool scanner determine that?

[gtstorey]

negative fuel trim is caused by the ECM seeing a rich condition and pulling fuel. Its reducing the fuel by 16/20% below what it has calculated it should need.

[jcdives]

Thanks!

I changed the spark plugs. LT Fuel trims are still at -20.