Terc doesn't like warm idle

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Turdcelbrother
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Posts: 28
Joined: Mon Jun 05, 2017 4:59 pm
My tercel:: 1987 tercel 4wd sr5

Terc doesn't like warm idle

Post by Turdcelbrother »

Hey all, up until yesterday my turd has been running great, however the car once warm wont idle at its normal 900 rpm it had before. The car will run perfectly fine when given gas and I have been able to just barely get to and from work by keeping my foot over the gas when not in gear. I'll be changing the spark plugs tomorow morning and I'll be poking around the carb as I have never fiddled with it, I'll check for vaccuum leaks and such but any help or tips would be very much appreciated. Thanks all!
xirdneh
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Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: Terc doesn't like warm idle

Post by xirdneh »

Check fuel cut solenoid on back side of carb. You can disconnect large green plug (with wires from carb) to expose terminal blades. Solenoid may be single or two wire depending on year. Supply positive juice to single or pos and neg to two wire. Listen for "click" . if no click its not working.
Love those Tercell 4x4 wagons but they sure suffer from road noise.
xirdneh
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Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: Terc doesn't like warm idle

Post by xirdneh »

Check vac lines for leaks, especially the one from base of carb to air filter housing.
Love those Tercell 4x4 wagons but they sure suffer from road noise.
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Mark
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My tercel:: 1984 Automatic, 1981 sedan
Location: Victoria, B.C.

Re: Terc doesn't like warm idle

Post by Mark »

The EGR vacuum modulator is only active when the engine is warm. It has a diaphragm in it that might be leaking, causing a rough idle when warm. That's what happened to me anyway. You could try disconnecting/plugging the vacuum hose to it and see if the idle improves.
Turdcelbrother
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Posts: 28
Joined: Mon Jun 05, 2017 4:59 pm
My tercel:: 1987 tercel 4wd sr5

Re: Terc doesn't like warm idle

Post by Turdcelbrother »

Thanks for the help guys! Is the egr modulator nearer the carb? Smaller circle piece, UFO shape almost?
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Terc doesn't like warm idle

Post by Petros »

yes, that sounds like it. It has a 12 mm dia tube that runs to the exhaust manifold that gets as hot as the exhaust, and it should have a vac line running to the UFO thingy.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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