[GRUF78]

Sir,

Sounds similar to my car:

2018 ZL1 1LE bought for track/DE events for wife. Oil pump failure at 6300 miles. GM replaced the short block. With new " engine", car uses 50% more fuel in a 20 minute track session (~9 gallons) than previously. At 6500 miles, left main cat fails and is replaced by GM. At 8500 miles, left main cat fails again-replaced by GM. At 9400 miles, left main cat fails again- replaced by GM. The engine has never been tuned. The car has an AWE track exhaust and a Rotofab intake and has since right after purchase..I.E,..the original engine ran with both of these mods for ~5K miles with no issues.

Additionally, after the new engine , the exhaust heat from the car has exponentially increased to the point of MELTING 3 sets of rear valance reflectors, the license plate illumination lamp and warping both rear tail light assemblies. Also, 2 sets of left bank exhaust bolts and studs have fallen out during this time. The black exhaust tips on the AWE exhaust have turned blue from the heat.

Dealer has run numerous diagnostics and all of the system and according to them, have checked good. They are trying to blame the aftermarket exhaust for the heat damage....


I believe the car is is over fueling a cylinder in the left bank somehow. However, the O2 sensors are good and no codes.

Thoughts? Thank you,

JM