Cosmo Kramer

Still chasing this one LOL! Did some work under the hood last night and testing different components. The hose going to the climate control manifold leaks down from 25 to 5 in about 30 seconds when the key is in the on position, when it is off it holds pretty steady. Would this be enough to cause a high idle (1100 rpm)? I can hear the plungers and stuff activating under the dash and cowl.

I also checked the EZ-F connector with an OHM meter for the idle switch and it is working properly.

Is there anything else I can check? How about a vacuum reading off the brake booster at idle? Will that number help tell me if I have a vacuum leak or not?

SharkSkin

Remove the hose that goes to the brake booster from the manifold end, and plug the manifold. Then see what your idle RPM is. That will give you the answer you want.

rixter

I just fixed (hopefully) a vacuum leak on my 87, was a tiny crack in a splitter and the idle was higher than yours, now it's normal again.... we're talking a TINY crack

Cosmo Kramer

I was tinkering looking for vacuum leaks. Pulled off the brake booster line and plugged with my finger, no change. Removed line from oil filler neck and plugged, no change. Pulled off hoses that run from the splitter at the back, have vacuum, no change when plugged.

The clue is, when I open the throttle I hear a whistle under the spider web in the throttle body area, happens as soon as I move the plate off idle and goes away when it is closed. Sounds like a vacuum leak, but is it?