Surge at an idle after car is warm?

[cgarym7]

I have just purchased a 92 laser turbo awd (all stock). The car runs fine while driving and has normal power but when i come to a stop in neutral there is a surge from 500-1000 rmp. I had tried replacing the o2 sensor but that didn't seem to help. Does any body know what might be causing this? Thanks.

 

[NOSNUSE]

Try unplugging the vacuum line from your EGR valve and holding your finger over the vacuum line.

 

[cgarym7]

Ok I will try that nonight as soon as get out of class. If that fixes the surge should I block the EGR valve or buy a new one?

 

[NOSNUSE]

If you don't have to worry about emissions inspections then just remove and put a block off plate on it.

 

[cgarym7]

I found it but there are 2 different vacum lines. Does it matter which one I block or do I need to block both of them to see if this gets rid of the surge?

 

[NOSNUSE]

I would just plug both off, but i believe it is the one that connects to the top of the EGR valve.

 

[Blu Divil]

Also you might check the idle switch. These are known to were out and getting corroded-dirty.

 

[cgarym7]

I tried plugging both of the egr vacum lines and it didnt help. Is there a way to test to see if the idle switch is going bad?

 

[Blu Divil]

Measure the continuity between idle position switch terminal and body ground.
Then stepping on throttle there should be no continuity between the two.