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Old 07-20-2012, 06:36 AM
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cobalt327 cobalt327 is offline
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Quote:
Originally Posted by starin View Post
so i found that my pcv valve grommet that leads to my carb is rock hard and probably leaking vacuum, it was getting late so tomorrow im going to buy a grommet and valve, hopefully this fixes my low idle problem.
Might as well get a new PCV valve if its old. Be sure the PCV hose is supple and not hard, too.

Most stock vacuum advance cans give more than 8 degrees advance at idle if hooked to a manifold vacuum source. Are you using ported of manifold vacuum for the vacuum advance? If you are unsure, try a different vacuum port for the vacuum advance and see if you get more advance.

If it's hooked to a ported vacuum source you might see some advance even though there's not supposed to be vacuum at idle from a ported vacuum source. You may see vacuum at a ported vacuum source if the throttle blades are opened more than usual for some reason. This is most often seen w/a performance cam that has low vacuum at idle, but can be seen w/a stock cam if there's a vacuum leak.

What type of cam do you have? Have you checked the vacuum at idle?
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