Contour Enthusiasts Group Archives Forums General Troubleshooting TH fix-problem

So, I love the TH fix, but after a week or so of daily driving, the computer, or something, goes wacky....when I come to a stop, the RPMs rise to 2000, then slowly settle back to idle around 1200.

If I remove the plug, start the car, shut it down, and put the plug back in, I'm good for another week or two, then it starts doing the high idle thing again.

I've tried resetting the computer with the plug in, and with the plug out, but the same thing happens...it's okay for a few days, then back to the high idle.

This is a pain in the butt...any ideas? Try a bigger hole in the plug maybe?

idle should be more along the lines of 700-800 rpms. sounds like u have a sticking iac valve.

I had the IAC valve replaced a couple thousand miles ago, before I did the TH fix.

This new thing has surfaced only since I did the TH fix. I can drive forever with normal idle behaviour (750RPM) as long as the TH plug is not in place. As soon as the plug goes in, within a few days, my "normal" idle becomes 1200 or so RPMs.

Unlike the high idle I had before replacing the IAC, which came and went, this new behaviour, once it starts, happens all the time....at least until I remove the plug again, and/or reset the computer. If I do that, it's fine for a few days, then starts doing the 1200 RPM idle again.

have u tried cleaning ur maf sensor?

I hate to sound like a broken record, but clean your throttle body. If that doesn't resolve your problem, I would suspect a possible glitch in the TP sensor.

When the throttle body is dirty enough, The adaptive strategy will no longer compensate fully. So clean the throttle body and pull the #4 & #7 fuses and see what happens. If you haven't cleaned it in a while, it probably needs it anyway.