1986 FJ60 Idle Problems

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Jun 20, 2005
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My '86 FJ60 runs fine at highway speed, but starts reving and eventually dies when in neutral.

My mechanic thinks it needs a carb. rebuild. Any suggestions?
 

chitown40

 
 
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Double D said:
My '86 FJ60 runs fine at highway speed, but starts reving and eventually dies when in neutral.

My mechanic thinks it needs a carb. rebuild. Any suggestions?
reving? or sputtering?

Need more info to help you out... Does your truck basically not idle at all?
 

FJ40Jim

The Cruiser Whisperer
 
 
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At the risk of oversimplifying:
Find a mechanic who can definitively diagnose what is wrong and what steps should be taken to repair it.
 
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I would check all the vacuum lines hooked to the inside of the carb and if you still have all the orginal vacuum hoses I would replace them with OEM or silicone hose. After I replaced mine it smoothed out the idle, there is less strain on the engine since it doesn't have to overcome the small leaks.

Check your idle speed too. I would focus on the carb.

Goodluck
 
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On it's own,while in neutral or with the clutch pressed, the engine revs up to around 3000 RPMS, slows down to 800 RPMS, revs to 2900, slows to 700, revs to 2800, slows to 600 and continues until it eventually idles down and goes dead.

We worked with the idle adjustment and made it where it won't idle low enough to go dead, but it still goes through this pattern of "pulsing".
 
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Double D said:
On it's own,while in neutral or with the clutch pressed, the engine revs up to around 3000 RPMS, slows down to 800 RPMS, revs to 2900, slows to 700, revs to 2800, slows to 600 and continues until it eventually idles down and goes dead.

We worked with the idle adjustment and made it where it won't idle low enough to go dead, but it still goes through this pattern of "pulsing".

the "idle" screw you were turning was it on the back top/bottom or on the front.
 

Mike S

 
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FJ40Jim said:
At the risk of oversimplifying:
Find a mechanic who can definitively diagnose what is wrong and what steps should be taken to repair it.
Jim has the right answer. Get someone who can put their hands on the truck can diagonose the problem and reccommend a fix. A lot of 'mechanics' these days only read diagnostic computer error codes, and almost never see a carb.

M
 
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If you are doing the work yourself, you may as well start from a known base -- this is my fail/safe: try doing a complete tune-up including a valve adjustment especially if one hasn't been done in a while. From there, you can start targeting specific systems, i.e. vacuum system, fuel delivery system, carb, etc... and making repairs as necessary until you find your sweet spot and the truck runs like a top.

A failure in one system or part may be masking others in related systems, so it really can come down to a matter of trial and error, through a logical process of elimination.

This doesn't answer your question specifically, but when there are so many variables at play, this is just one method that may help...

-dogboy- '87 FJ60
 

FJ40Jim

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The engine can't run up to 3K RPM with the throttle closed. Therefore there is either something opening the throttle on the carb, like the AC idle up pot that is inadvertently connected to the EGRVM, or else there is another large source of intake air, like a leaky brake booster or...?

Double D said:
On it's own,while in neutral or with the clutch pressed, the engine revs up to around 3000 RPMS, slows down to 800 RPMS, revs to 2900, slows to 700, revs to 2800, slows to 600 and continues until it eventually idles down and goes dead.
We worked with the idle adjustment and made it where it won't idle low enough to go dead, but it still goes through this pattern of "pulsing".
 

dd113

 
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I just had a 60 doing exactly that you describe. The AC idle up was working but too well; the AC solinoid was not working correctly and was "pulsating" the vac so it would go up then down.

Does this happen all the time or just when the AC is on?
 
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Jun 20, 2005
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It has always "pulsed" slightly when the AC was on and in neutral.

Whats happening now is much more exagerrated and doing it when the AC is off.
 

Pluton

 
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Oct 12, 2004
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At least get the Emissions Manual and make sure all hoses are hooked up correctly. If you have the time, it's cheaper to do this yourself rather than at $60/hour for the tech. If you don't have the time, do as Jim C. advised: find a tech w/ smog-era carb knowledge. Good luck.
 
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