2003 MT High Idle

[Sturdevant]

2003 Turbo MT 105,000 miles, Stage 1.

The idle speed at rest has increased to about 1500 RPM, however when I am coasting to a stop in neutral or with the clutch in the idle speed is about 2700. When I come to a complete stop it goes down to 1500. There are no error codes.

Any ideas?

[littleblueGT]

Check to see if you blew off a vacuum line, and there are a lot of them!

[bobs turbo pt]

i agree some sort of vaccum leak

[Sturdevant]

I agree that it seems to be a vacuum leak, but I can't find anything.

I removed, cleaned and replaced the Idle Air Control Valve, no help. I disconnected the IACV and it made no difference.

I checked for codes with the on-acc-on-acc-on trick and got
P-0508
P-0633.

which don't seem to be listed.

I might try replacing the IACV.

[littleblueGT]

Do you have the plastic intake manifold? I had one that split at the seams causing a vacuum/boost leak. I found the leak by using bubble leak tester which is just a soapy solution with a fuzz ball applicator. Just apply around the seams and rev the engine, if you have a leak you will see bubbles.Did you reset the computer?

[Sturdevant]

I have the aluminum manifold, but I'll try the leak test. I forgot that the manifold is under pressure. (Turbo, duh)

I did not reset the computer. How is that done?

[CREWZIN]

P0508 = "Idle Air Control System Circuit Low"

P0633 = "SKIM KEY NOT PROGRAMMED IN PCM"

The SRT guys say that the 0633 is nothing to worry about with engines that are upgraded with "stages" ( PT's only have Stage 1, SRT's have multiple Stages).