I’ve got a 2002 with the F23A1 and I’ve been having an issue when I start the car no matter how long it has been sitting it will run rough at idle and if I try to drive it will sputter at about 2500rpm but all issues go away once it warms up and comes out of open loop. I’ve got codes for 02 sensor voltage low and a fuel mixture lean. I don’t believe it has to do with the 02 sensors as it’s only during warm up when it’s disregarded. I also don’t think it’s egr related because it all seems to do with temperature the colder it is outside the worse it will run until warm and if it was egr wouldn’t it just be and no matter the temp?

 

In the mean time until you find the answer, try running some Sea Foam through the fuel system and see if it is just a dirty cold start issue.

 

I did last week and ran a tank full through with it in and another half a tank of 91 without last thing I’m gonna try is see if my new job has a smoke machine and check for vacuum leaks as I got that lean code and really can’t figure this out also does anyone know what map psi should be reading at idle shop was around 65-70 and it’s reading 3.5-3.9 psi everything I see is in InMg