i have a boosted c5 motor running a t3/t4 turbo about 10psi boost. the only problem i have is for no reason everyday my check engine light kicks at least once. the performance of the engine stays the same and runs like it should and after restart its off wtf who knows what this is.

 

You haven't pulled the diagnostic codes?

 

no it wont stay illuminated long enough to if i shut down and restart its gone.

 

the ecu still stores the code. also you can pull the code with the car running. so check it out and report back with the code and we can go from there

 

If this were 10 years ago i'd tell you to put another check valve before the map sensor, it sounds like it's seeing boost.

Check the code. Also what are you using to tune it?

 

the map sensor was trippn out because of boost. switched out the stock for a 4 bar map sensor no problem now haha...