I have been dealing with misfire issues all summer I have tried damn near everything but new fuel pumps and wiring harness.

I have tried, several different coil on plug setups, injectors, ecus, cam and crank sensors, new map sensor.... Nothing seems to fix it.

It happens almost every time I get into boost and sometimes it's 2nd gear sometimes happens in 3rd sometimes in 4th. Usually higher up in rpms but not always at the same place or same gear.

I'm lost, I'm ordering a wiring harness Monday and other than that besides fuel pumps which I'm not sure are the issues as my air fuels are good and fuel pressure is good I don't know what to try next.

Anyone ever had a wiring harness cause misfires??

 

I'm not trying to insult your intelligence, but assuming you've gone through several cop setups, did you change the plugs? Check your TPS and IACV. It's probably something stupid simple.

 

Haha yes everything else is good. Plugs were the first thing that got changed. I figured I didn't even need to mention them!

 

Have you done a boost leak test? Have you done any logging? Im assuming your tuned, but you could be hitting load limit or something like that

 

This could be pretty far fetched but I had a friend that had lots of misfire issues under boost and even the tuner was baffled. Turns out the alternator was on its way out and the vehicle would have low voltage due to the alternator not having any output only under boost. The lack of voltage/amperage caused the fuel and ignition systems to work poorly and misfire.