High Idle Start

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Mar 28, 2003
Nashville, Tennessee
I just cannot get comfortable with my high idle start on my '96 FZJ-80. Does anyone else have the hair on their neck stand up when they here the metal in their motor for a second or two before the oil really starts flowing on a cold start up? I am sure it is the way it is supposed to start, but I just cannot imagine it being very good for the motor. I will not question the engineers from the land of the rising sun.


If it really bugs you, it is possible to remove the idle air control and stack a couple o rings on it to limit travel. The procedure is outlined on the 80's cool tech page.

Make sure to use two o-rings. I used one, and it didn't make a damm bit of difference. Funny, but at the local parts house where I bought the o-rings (this is a real parts house, not a Pep Boys), the guy asked what I was doing. I explained. His comment, all toyota's do that, they last forever, don't worry about it.


Has anyone who has done this fix ran into problems with the ECU not adapting to the new setting?

After adding the rings, the cold start up was where I wanted it (1,200 rpm). However, after warm up, stalling would occure and could not maintain the warm idle of 600-650 I was used to.

Suggestions included drive for prolonged time changeing speeds, to resetting EFI fuse, to starting and stopping engine a number of times to allow the ECU to "learn" the new parameters. None of these worked.

Am I missing something or does my truck just not like to be messed with in this way?


94' 115,000
My thought would be that perhaps the air valve is not sealing all the way and you now have a vacuum leak. The computer should adapt in only a few minutes to any changes. I would pull the valve again and check the seal.

Unplugging the IAC causes it to "loose it's mind". The engine will need to go through several start-up cycles for the IAC to re-learn (as many as 10 or 12).
Thanks for the reply.

Tried restarting at least 20 times. CDan, is just the plunger available, if what Cary suggests is true?

I have run all tests for IAC valve and it checks out OK


94' 115,000

When I pulled my IAC just out of curiosity a while back (I was in "curious" mode), I found it had quite a bit of carbon-like buildup on it. It was surprising to me that it still sealed. Some solvent and a clean rag cleaned it up good as new (I think anyway). The plunger seemed to be made of a material that resemble graphite--it's may be some very hard rubber compound. In any case, after cleaning the plunger and cleaning the mating surface on the TB, it went back together fine and has been working ever since without any trouble. If you think your's is gunked up, just try cleaning it first. If that doesn't work, you can always feed Dan's doggies. :D


Thanks for the suggestion. I'll try that first. As for CDan suggesting starting and restarting 10 to 12 times, I wonder if he is overstocked on starter contacts. Just kidding Dan.
We did this fix to my Son's ( 95 FZJ80 ) worked great. It did take a few starts for it to adjust. We did use 2 o rings, and the lock tite for the three little screws. When he had it in for a tune-up, the tech did mention, that his diagnostics showed that the IAC did not operate the full stroke :doh: My Son explained why, and he had never heard of this fix before :D

Not sure why it did not work on yours ???

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