LiqTenExp

2017 ZL1 with H/C/LT and 2300. Cylinder #3 has started reporting misfires. It is fine at idle and heavy load, issue exists at light loads. Issue is worst when cold and goes away when fully up to temp. Have already:

• replaced plug
• replaced plug wire
• swapped coil pack
• inspected under valve cover (didn't observe anything like cracked springs or hot spots on top of valve, everything's tight)

Take a listen while watching this log go by and see if you can come to a conclusion:



Attached is a photo off log when car is fully up to temp, notice no more misfires comparably.

minytrker

iTrader: (13)

Do you run E85? We had a new Z06 few months ago with heads, cam and whipple that acted really similar and it had really dirty injectors. We cleaned them and them and one failed in the machine. Replaced that one injector and its been good ever since.

LiqTenExp

No, but did run Boostane last year, quit this year and switched to Meth, could be a source of crud.

LiqTenExp

Plan so far is replacing injector(s), anyone else have any other thoughts?