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I noticed soemthing the other day.. I pumped my brake when the car was at idle (in park) and noticed that my idle started to become rough and the vacuum became less...

Usually my car idles around 7-800ish... and then it started bouncing around +/- 300rpm.... and my vacuum which is usally at -.60bar went to -.50 bar...

Any suggestions to why this happpened.... I checked the level of my fluid and it seems normal... checked for any leaks and found none....

I want to find out the problem since I have a wrranty before I do my brake lines and etc...
 

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This happens if you pump the brake too much. I think it just messes w/ the idle air control valve, I wouldn't worry about it too much, just don't pump you brakes a bunch of times when you're sitting at idle. What's the point of doing that?
 
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Discussion Starter #6
correct.. there is no point in doing it.. but I was worried that it could be showing me another problem...
 

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greensoup said:
You brake lights need power. To the power the ecu increases the idle on the car. Thats probably all that it is.
The idles drops, doesn't increase. If that were the case then you'd better get a new alternator.

The brakes are power assisted by a big brake booster that runs off of vaccum. This is actually th only part of the entire systme that stays in constant vaccum (even under boost). What I think is happening is that when you are pumping the brakes you are robbing vaccum from the Idle air control which is in close proimity to the brake booster and causing it to act funny. Yo may want to clean out the idle air control as a normal part of maintenance. While it can wear out over time, its really only for convenience (racing manifold will not have one). I don't think that what you're experiencing is indicating any serious problems.
 
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