Okay, here's the whole story... I have had my '90 IROC-Z for about a month. I 've been trying to fix minor things and tune it up, etc. While replacing the oxygen sensor, the manifold got stripped out I ran it for 2 days without an o2 sensor. Well, I took it to a shop today and dropped it off. They re-tapped the manifold and installed the new sensor (only charged me $20) so I was happy... Well, I drove the car about 5 miles and it was sputtering around and trying to quit. I pulled in at my buddies house and noticed that the garage had left a plug wire off, when they were tapping it So I put it back on and drive home. I raised the hood and was going to adjust my IAC. I started the car just to see where the RPMs were before I started. I noticed a loud 'whistling' noise coming from around my oxygen sensor or alternator or something in that area. When I give it a little gas, the noise goes away. Could this be a vacuum leak? Are there any vacuum lines around the o2 sensor that they may have 'forgot' to hook up like the plug wire? And here's fuel for the fire I tried to adjust my idle (like the tech article says)... however, my car will not idle below 1200 RPM!!! I have the minimum air screw backed all the way out, and I tried to press the throttle back farther. It is out of room...

Anyone have any ideas?

-Thanks

 

Was it idling at 1200 before you did the adjustement procedure?

 

Yes, it has always been that high... I never did the IAC adjustment procedure.

 

Okay, I printed out a vacuum diagram and checked EVERY vacuum line I could find. All of them were in place. Finally a can of WD-40 came to the rescue... I used it to find a leak in the gasket between the throttle body and the plenum. Gonna replace it tomorrow.

 

i normally use starting fluid.. wouldnt wd-40 make a bit of a mess?