High idle 2k RPM

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ToeKnee805
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High idle 2k RPM

Postby ToeKnee805 » Thu Mar 12, 2015 8:32 pm

Rebuilt Bluetop Largeport with EGR Eliminated.

When cold i turn my car on cold it idles at 2000RPM. I drive it around the street and the idle stays the same.

Already checked for Throttle body stuck open and i force it closed with my hands(At the pulley) and nothing happens.
One thing i do notice is that the dash pot sucks in the throttle stopper and the throttle plate doesnt even come close to it (is that normal?)
Checked for vacuum leaks with brake cleaner and everything checks out. I have the PS idle up blocked off cause the PS is removed. I have a AC idle up still hooked up eventhough my AC is gone. If i unplug the AC idle up nothing happens, along with the lil green valve by the AFM.


Only thing that recently came to mind is to bleed my coolant completely Cause the IAC may not be warming up? Other than that im all out of ideas.
1986 Corolla GT-S -- Unmolested -- Now Resto Project
1985 Corolla GT-S -- Turbo Levin Track Car
1982 Corolla 1.8 -- Sitting collecting dust

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jondee86
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Re: High idle 2k RPM

Postby jondee86 » Fri Mar 13, 2015 10:17 am

How did you block off the P/S idle-up lines ?? If you looped them together with a short
piece of hose you will have a permanently high idle. They need to be capped off individually.

Cheers... jondee86
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yoshimitsuspeed
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Re: High idle 2k RPM

Postby yoshimitsuspeed » Fri Mar 13, 2015 11:06 am

There are a few different idle up valves.
I assume you mean Power steering right? If so then that and AC could both just be blocked off and be fine.
I assume jondee86 is talking about the IACV which does need coolant flow to it. If this is not hooked up or if there is a blockage, air bubble or anything else preventing flow through it your idle will remain high.
If the IACV coolant lines are hooked up then once the car is warm make sure the coolant flowing through the TB feels about the same temp as the big coolant hoses.
If that is getting operating temp coolant and the idles still doesn't change from cold to warm that valve may be stuck or nonoperational.

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ToeKnee805
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Re: High idle 2k RPM

Postby ToeKnee805 » Fri Mar 13, 2015 11:29 am

After looking at my engine closely I found out I have an FX16 rear water outlet behind my head, and the coolant line that flows to the throttle body is capped off. From the rear housing I only have 1 big hose running to the heater core and the small one isn't there(that goes to the wp and tb) I haven't tested anything but I believe that's my culprit. Will running an iac Blockoff plate fix my issue, since it's cheaper than buying a rear coolant housing. And I live in CA where our throttles don't freeze.
1986 Corolla GT-S -- Unmolested -- Now Resto Project
1985 Corolla GT-S -- Turbo Levin Track Car
1982 Corolla 1.8 -- Sitting collecting dust

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Re: High idle 2k RPM

Postby yoshimitsuspeed » Fri Mar 13, 2015 11:48 am

A blockoff plate would work. Even in CA on a cooler day you may have to give it a tad of throttle for a min on startup.
Also remember that it doesn't have to be below freezing for a throttle to freeze. A throttlebody is a venturi and as such can greatly cool the air as it passes through.
Now the chances are pretty low that anything could/would ever happen but personally I wouldn't risk it.

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jondee86
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Re: High idle 2k RPM

Postby jondee86 » Fri Mar 13, 2015 12:15 pm

yoshimitsuspeed wrote:I assume jondee86 is talking about the IACV....

Nope... I was talking about the permanent high idle that comes with looped P/S
idle-up tubes on the IACV. But the result is exactly the same as the situation you
describe with an ISCV that never heats up (and therefore never closes). Both result
in a roughly similar high idle speed.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

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Re: High idle 2k RPM

Postby yoshimitsuspeed » Fri Mar 13, 2015 1:26 pm

jondee86 wrote:
yoshimitsuspeed wrote:I assume jondee86 is talking about the IACV....

Nope... I was talking about the permanent high idle that comes with looped P/S
idle-up tubes on the IACV. But the result is exactly the same as the situation you
describe with an ISCV that never heats up (and therefore never closes). Both result
in a roughly similar high idle speed.

Cheers... jondee86


Crazy. I have never had a 4A with power steering lol. Didn't know that system was that complex.
Thanks for the info.

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ToeKnee805
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Re: High idle 2k RPM

Postby ToeKnee805 » Fri Mar 13, 2015 1:30 pm

@jondee haha yeah I did that back in the day. Looped PS lines are no fun. They're capped off correctly.

@yoshimitsu thanks for the input dude! I'll search for a rear housing if not I'll go Blockoff route
1986 Corolla GT-S -- Unmolested -- Now Resto Project
1985 Corolla GT-S -- Turbo Levin Track Car
1982 Corolla 1.8 -- Sitting collecting dust