Bouncing Idle on startup, 3.2

[josephvman]

My 3.2 Targa started acting up the other day, with the idle bouncing on cold start, and hanging up above idle after revving it. The car has a SW chip, MK cat bypass and sport muffler. It seems like it went from running perfectly to this, and I noticed it after washing it. I didn't get the engine compartment wet at all, but opened it to wipe it down. I'm guessing I may have pulled something, created a vacuum leak, or done something to the idle control valve. I just had an oil service a couple hundred miles ago. It gets better once it's warm, but still doesn't feel exactly normal to me.

Here's a video clip. I'm revving it about halfway through the video, and you can see the revs hanging around 1200-1300. Idle typically 800-900.

[cabmandone]

If it just happened after you washed the engine bay, the first thing I'd so is double check all electrical connections. I bumped my CHT connection once and went from running well to crap in the blink of an eye.

[Jeff Alton]

ISV may need cleaning. Or, and adjustment to AFR is required. May also have a vacuum leak.


Cheers

[Matt at Pelican Parts]

I would recommend starting with checking along the intake. It behaves sort of like a vacuum leak. You could smoke test it and look for anything obvious.

-Matt