93 High Idle

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Oct 11, 2014 | 09:44 PM

charliet615

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Racer

Joined: May 2012

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93 High Idle

I may have a vaccum leak that is causing this.. What is the best way to check all vaccum hoses? Idles at about 800 rpm's.

Oct 12, 2014 | 02:53 AM

Cliff Harris

Race Director

Joined: Apr 2002

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From: Anaheim CA

Check out the vacuum hose diagram on the radiator shroud. Find the source for each vacuum line and plug it temporarily while the engine is running.

The vacuum check valve under the passenger side injector cover is a known trouble spot. About $4 at any auto parts store.

Oct 12, 2014 | 10:49 AM

charliet615

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Racer

Joined: May 2012

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Thanks, i'll check that out today..I've heard that you can spray starter fluid at the vaccum line connections and watch for a rpm change?

Oct 12, 2014 | 12:02 PM

92ragtop

Melting Slicks

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From: Delta B.C. Canada

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Quote:

Originally Posted by charliet615

Thanks, i'll check that out today..I've heard that you can spray starter fluid at the vaccum line connections and watch for a rpm change?

Make sure that you have a fire extinguisher handy if you do that.

Oct 12, 2014 | 12:40 PM

charliet615

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Racer

Joined: May 2012

Posts: 392

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Yes, i have several fire extinguisher's handy, but is this a good way to check for vaccum leaks?

Oct 12, 2014 | 01:29 PM

FrankieD

Burning Brakes

Joined: Mar 2005

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From: Richmond Hill Ontario

You can use one of those portable handheld propane torches ( like the plumbers use to solder pipes) and just open the valve and go around various engine spots until you see RPM change.