firebird idle too high?

[Joe]

Hello everyone,

I have a nasty problem here, hopefully you guys can help, I have a '93 pontiac firebird (manual). The minute I start it up, the idle shoots straight up to 4000 rpm. Before, it used to go only up to 1,500 before I removed the intake manifold to replace my gaskets. I made sure all of my gaskets are in properly to avoid any leaks, but still nothing. Is there anything you guys can help me figure out for this? thanks!

 

[wde3477]

Given that you've removed the intake manifold - would first suspect a vacuum leak somewhere - perhaps not with the manifold itself, but perhaps the hoses and miscellaneous stuff that connect up. One way to check would be to CAREFULLY spray carb cleaner around the area to see if the speed picks up. However, to be going to 4,000 RPM - it has to be a serious leak - perhaps better found through other measures such as careful inspection and listening with a mechanics stethoscope.

Other thoughts are whether the Idle Air Control solenoid is working properly, or if something happened to the main throttle body butterflies where they are not closing to their original stops.

Good luck, and keep us posted on what you find.