Idle issue?

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BALDYMONSTER
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Idle issue?

Post by BALDYMONSTER » 10/02/18 18:55

So I stopped at the local shop to get some bits before I went home and when i did the car sat at 2000 rpm.

Drove it home and it seemed fine as I drove but when I parked up it sat at 2000 rpm again.

I have noticed that if it's at idle from cold, about 5 mins later the revs can suddenly drop and then it idles properly again, is this related?

Car is a UK non turbo 1993.

Any ideas folks?
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Re: Idle issue?

Post by abovetherim » 10/02/18 19:38

2 possibilities jump out at me. First is throttle cable or butterfly in the tb sticking. Second would be IAC valve sticking.
With the engine off have a look at the cable and brackets etc paying attention to the end of the sleeving also. Then by hand work the linkage to check for smooth free operation. Pop off the intake tube and see that the butterfly closes when throttle off. If all this checks out then it may be time to whip the IAC valve out for a good clean
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Re: Idle issue?

Post by BALDYMONSTER » 10/02/18 19:42

OK, what is and where is the IAC valve?
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Re: Idle issue?

Post by abovetherim » 11/02/18 11:50

Idle air control valve. Attached to the throttle body. There will be 2 small coolant lines running to and from it as well as an electrical connector.
A bit of a pain to remove so check the cable first.
The IAC can be checked of the car by applying 12v and seeing if the flap moves. This flap/barrel can get gummed up but can be cleaned with carb cleaner.
1991 rev 1 T Bar n/a 3sge import. A work in progress!!!

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Re: Idle issue?

Post by BALDYMONSTER » 11/02/18 12:52

abovetherim wrote:
11/02/18 11:50
Idle air control valve. Attached to the throttle body. There will be 2 small coolant lines running to and from it as well as an electrical connector.
A bit of a pain to remove so check the cable first.
The IAC can be checked of the car by applying 12v and seeing if the flap moves. This flap/barrel can get gummed up but can be cleaned with carb cleaner.

Thank you buddy, could you post a pic up of where it is?

I think I have got it but I want to make sure.
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Re: Idle issue?

Post by abovetherim » 11/02/18 20:43

Sorry dude i have no photos of the location but if you watch this vid you will see what it looks like and how to test


If you remove the intake tube off the throttle body, just below the TB you will see the IACV.
1991 rev 1 T Bar n/a 3sge import. A work in progress!!!

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Re: Idle issue?

Post by BALDYMONSTER » 11/02/18 21:19

Thanks buddy, I’ve got the right thing.

Hope it just needs cleaned.
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Re: Idle issue?

Post by abovetherim » 11/02/18 22:29

Did the throttle cable check out ok?
1991 rev 1 T Bar n/a 3sge import. A work in progress!!!

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Re: Idle issue?

Post by BALDYMONSTER » 11/02/18 23:21

abovetherim wrote:
11/02/18 22:29
Did the throttle cable check out ok?

Yes mate.
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BALDYMONSTER
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Re: Idle issue?

Post by BALDYMONSTER » 14/02/18 21:14

This is it?

I might try spraying some carb cleaner down it first although it hasn’t done it again.



Image
Well those are my principles, and if you don't like them... I have others.

A child of 5 could understand this! Quick, send for a child of 5!

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abovetherim
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Re: Idle issue?

Post by abovetherim » 15/02/18 16:49

That may have some effect but obviously without the engine running.
I do doubt if the cleaner will get to where it's needed tho. If you look at the pic or video you can see the barrel that gets gummed.
1991 rev 1 T Bar n/a 3sge import. A work in progress!!!

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