Alright my mustang was supercharged and now I returned it to stock. The only thing left on my car from the supercharger was the fuel pump. Now the problem is my car is throwing 4 codes. You got the two codes for the long tube headers saying they are slow to respond. The other two I am worried about are p2195 and p2197, stuck rich and stuck lean. The car runs fine but it gets about 100 miles a TANK. Its just eating the fuel I guess to compensate for it running lean? I have a fuel pressure gauge and when you first start the car and for about 10 minutes it will be at about 25psi, then out of nowhere it will shoot up to about 60psi and stay there. Thats when the car starts running a little weird and the idle starts going up and down. I replaced the 38lb injectors with some brand new OEM stock 19lb injectors, fuel filter is brand new, I just cant think of what it could be. Maybe a bad MAF? Bad ECU? Any help would be appreciated

 

Car has been flashed back / chip removed to stock tune??

 

Sounds like you need to re tune the a/f ratio.

 

returned the ecu to stock flash, and then had the shop write me a tume for the gears and headers, but still got this problem

 

Nobody has any advice on this