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Old 04-02-2010, 02:36 PM
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Originally Posted by beertracker
I am using the two stock return springs that came with the car. I applied hand pressure to the throttle to slow the engine down but it didn't slow down.

I will look for a vacuum leak next. Last Fall the engine always idled around 1000 rpm and I never fixed it. This Spring I had the carburetor off and after I replaced the carburetor I noticed the engine idling at 1500-2000 rpm. So this may be related to vacuum leak. I haven't check the vacuum advance or taken the car for a test drive. It is a automatic trans. The car has power brakes so how can I tell if the booster is leaking? Just do a brake check and see if power brakes work? The booster is original to the car 1970.

Thanks for the ideas.

Usually, just pumping the brakes will give an indication of a bad diaphragm, there will be a "whooshing" sound sometimes, sometimes the idle speed will change, and the brakes won't work as they should- but you'd have to drive it to know that last part. If you DO drive it, be REAL careful that you have plenty of room to stop in the event the brakes give out on you.

I'd tend to think the base gasket might be the fault, or one of the vacuum lines is off or broken/split- that sort of thing.

If you have a vacuum gage, you could hook it up to see if you're getting a low reading.

More on interpreting vacuum gages:
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