Cascade Crew

Al Hasse · Posted: Mon Apr 07, 2008 6:13 pm Post subject: Idle issues

Seems that Friday night the 92 V6 started to idle at about 1300 after the motor is warm. Thought nothing of it at the time since I was warming the car up and defrost was on high. This morning idle was back between 800 and 900 after warm up and the car was running fine. Now, this afternoon on the drive home it's at it again, 1300 - 1400 idle and temp in the 180 - 190 range. I shut down the A/C (defrost) and turned off the fan and didn't change anything. Acceleration while rolling sometimes stumbles a bit, then picks up. So far it's not given me any engine codes so the ECM seems to think everything is OK for now. I haven't found any vacuum leaks yet, but I'll keep looking. What other things could cause this idle to be high??? The motor has about 25,000 miles on it, I'm not sure about some of the sensors, most (except the knock sensor) were kept from the old motor.

This is kind of an inconvenience because it's the only car I have that is drivable at the moment....

Twilightoptics · Posted: Mon Apr 07, 2008 7:32 pm Post subject:

Reeks of vacuum leak.

Possibly a stuck IAC.

Al Hasse · Posted: Mon Apr 07, 2008 7:55 pm Post subject:

I'm thinking it may be too. A while back when I had the upper intake apart to change injectors, I cleaned up the IAC passages and broke the gasket. I put a thin layer of RTV on both sides and it's been doing fine until now. I'll look in that area first. thanks.

blue89 · Posted: Mon Apr 07, 2008 8:13 pm Post subject:

Never came back down huh? Think you could spray the gasket down where the crack is with brake kleen to see if it effects the idle?

Al Hasse · Posted: Mon Apr 07, 2008 8:21 pm Post subject:

Worked OK this morning as far as I could tell. This afternoon it acted up a bit. Gas mileage was down a bit too.

Al Hasse · Posted: Fri Apr 11, 2008 6:06 pm Post subject:

I cleaned out the IAC passages again as well as the pintle on the IAC itself, they were pretty sooty. Still hasn't changed anything. I can't find any vacuum leaks. Oh, yeah, she died on me when I tried to accelerate away from a stop sign this afternoon, kind of like it lost fuel.

I turned off the A/C compressor to keep the load off the motor, still idled high, but I noticed the fan didn't come on until the temp was over 225* and mine is set to about 215* (thanks to Dyno Sources and Zac). I turned on the A/C to turn on the fan, then off again, the fan stayed on until the temp went down to 200*. Then a strange thing, my idle went to normal, the fan kicks on at 215* and off at 200*. I was thinking that maybe the CTS might be going bad (I know when they go, they normally go all the way at once). I had one go bad a few years ago, and some of the symptoms are similar, but it threw an engine code.

Al Hasse · Posted: Mon Apr 14, 2008 6:24 pm Post subject:

Seems it was the IAC after all. After I cleaned it up and adjusted it, I took it for a drive and everything seems to be OK so far.