Cold idle speed

GMGOOCH

MEMBER
1985 TOYOTA MR2
4 CYL
2WD
MANUAL
140,000 MILES

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.
Thanks
Guy

Sunday, November 21st, 2010 AT 4:48 AM

6 Replies

JACOBANDNICKOLAS

MECHANIC
109,724 POSTS

You are taking me back a few years. Does the vehicle have TBI or a carb?

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Sunday, November 21st, 2010 AT 4:52 AM

DR LOOT

MECHANIC
2,311 POSTS

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.

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Sunday, November 21st, 2010 AT 4:54 AM

MMPRINCE4000

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8,548 POSTS

I believe the original MR2 had the 4AFE FI engine.

An idle that high is usually a vacuum leak.

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Sunday, November 21st, 2010 AT 1:28 PM

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
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Sunday, November 21st, 2010 AT 6:41 PM

GMGOOCH

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2 POSTS

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?