cold idle speed

1985 TOYOTA MR2
140,000 MILES • 4 CYL • 2WD • MANUAL
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GMGOOCH
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my 1985 MR2 idles very fast untill it warms up. @35 degrees F it idled @3500 rpm. How do I slow it down. When warm it idles @ about 1000.
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Guy
Nov 21, 2010 at 4:48 AM
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JACOBANDNICKOLAS
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You are taking me back a few years. Does the vehicle have TBI or a carb?
Nov 21, 2010 at 4:52 AM
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DR LOOT
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I believe on the throttle body cable just below it you will see a small round vacuum diaphragm there will be a hose going to, check and make sure it is holding vacuum,
Nov 21, 2010 at 4:54 AM
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MMPRINCE4000
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I believe the original MR2 had the 4AFE FI engine.

An idle that high is usually a vacuum leak.
Nov 21, 2010 at 1:28 PM
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DR LOOT
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I believe I answered this question before there were some updates on the site I do realize it was in 1985 but you're probably correct its a 4AFE FI engine, we will probably need some more information
.
Nov 21, 2010 at 6:41 PM
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GMGOOCH
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thanks for the reply. I don't know if I am supposed to answer here but can't find any place else. The MR-2 is fuel injected. I have it stored for the winter so can't check for vacumn leaks now but will this coming spring. I was wondering if it could be the air bypass valve just below the throtle body. It has coolant flow through it to cut back the bypass as it warms up but wonder if it could be too open when cold?
Nov 21, 2010 at 7:26 PM
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JACOBANDNICKOLAS
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The bypass can cause this type of problem. Check for vacuum leaks too.
Nov 22, 2010 at 1:26 AM
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