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Old 12-20-2004, 02:24 AM   #1
skokie
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Idle Problem

When the truck is at idle and I press the brakes after about 2-3 seconds the idle drops from 750 to 500 and the truck seems like its fighting to stay running. I let off of the brake and the truck idles back up but there is a smell that comes along with it? I have a 350 with a new power booster, mc and check valve. I recently painted the booster and mc. Any ideas on whats going on?

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Old 12-20-2004, 02:26 AM   #2
jhow66
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Booster has vacuum leak.
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Old 12-20-2004, 02:28 AM   #3
skokie
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Quote:
Originally Posted by jhow66
Booster has vacuum leak.
Think a new check valve would be a good place to start?
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Old 12-20-2004, 12:15 PM   #4
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Worth a try.
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Old 12-20-2004, 01:36 PM   #5
skokie
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I will try that tonight.

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Old 12-20-2004, 02:48 PM   #6
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If that does not work try removing the the line to booster and plugging. then try brakes -if it does not change idle has to be in booster.
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Old 12-21-2004, 01:57 AM   #7
skokie
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I think I got it. I replaced the rubber seal and check valve. That helped somewhat but what fixed it completely was me adjusting my carb. I think I had it a little too lean. A quarter turn on each side of the holley did the trick. Also the original rubber check valve seal was very flimsy. The replacement was not.

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If you want to know more about rare forms of pediatric cancer or if you want to help fund pediatric cancer research, please check out the website for the non-profit I started.
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