kowalczyk86

89 Mustang 5.0

Check engine light has been coming on/off for the past month or so. It only seems to come on when I accelerate, and then immediately turns off. At that it doesn't ALWAYS come on when I accelerate, just sometimes.

My buddy ran KOEO test (not sure why he didn't do a test with ER), and we got codes 13 (Cannot control RPM during ER Self-Test low RPM check/ECA could not lower idle speed. Suspect Idle Bypass valve problems. KE15), and code 67 (Neutral safety circuit failure {A/C was not on}). I read online to not worry too much about the code 67 (btw my car is a 5 speed)...? Now that I think of it, the clutch was in 1st, so that may be why it pulled a code 67..

Car runs top notch from what I can tell. 15k miles and only mod is BBK cold air intake. I am thinking maybe this has something to do with it or else the MAF sensor?? I took the sensor off and cleaned it as best I could (there is a little bit of white residue, but not much).

I am just wondering if someone can guide me in the right direction. I want to get this fixed, and I would like to do it myself if at all possible. If I do have to end up taking it to a mechanic, I want to know exactly what the problem is so that I don't get ripped off.

I have a complete exhaust kit coming soon, but I do not even want to think about that until I fix this problem..

Cold idol is around 900 RPM - it is right around there, maybe a little higher when it is warm.

Any help is appreciated.

Shawn

Bubba 95SN

SBFTech...go there do the tests yourself and post results. Keep clutch depressed during test will eliminate code 67. Koeo fix first, KOER next,KOEM last. Seeing how the problem happens while running the run test seems best. Oh, do fuel pressure test.

kowalczyk86

Replacing IAC tonight - we'll see if that works.