Hello, I just bought a 89 Raider yesterday and need to get it smogged here in California. Problem is it idles too high at about 1500rpms to 2000rpms. It doesn't always idle high from what the previous owner told me. He also said he replaced all the vacuum hoses, and it wasn't a vacuum leak. There was one other thing he told me he replaced in the throttle body but I cant remember exactly what it was but will know here real soon. He also said that he thinks i'll have to replace the throttle body to get it to idle correctly. To be honest I don't really know much about working on cars and what not but thought maybe one of you might of had this problem in the past and might have a solution. Thanks!

This thread just help me fix my V6 high idle problem http://www.4x4wire.com/forums/showflat.p...p;vc=1&nt=2


9 time out of 10 it the IAC There is a few on ebay right now for 40 bucks

Sounds like maye the PO did the IAC. Try pulling the Factory Service Manual "raider_fsm_1989_powertraindiagnostics-30l" that is on the site in my signature.

thanks man, i'm looking into it now!

Ok, I think the previous owner already replaced the IAC. Is there anything else you guys think could causing the high idle? Is the previous owner right about needing to replace the throttle body? Thanks!

If ICM was replaced, maybe he droped the o ring off it.
Make sure your thermostat is a 195o. Any less and your Engine control module thinks the engines cold.
The brass thing sicking out of the front of the manifold with 2 terminals in the water temp sender to the ECU. Sometimes these go bad.
If the battery has been disconected for more than 10 seconds the ECU goes back to default and will run high idle. The cure, in the electric vol. of FSM, is to let it idle 5 min. Shut off, then restart and let it idle another 5. Each time you do that idle goes down a couple hundred rmps. 2 or 3 restarts should do it.
Other possible defect is a crack in the EGR tube.
My Trottle body has 250,000 and 24 years on it and it's still good enough to pass CA smog. They are better made than most other brands,,,like most of the qualities you will find with your '89 Mitsu.

Thanks CrzyDav. I've been trying to look into the ICM but can find anything mentioned about it in the FSM's. By ICM you mean Ignition Control Module?

Also, I'm going to open up and take out the thermostat...how do I know if its a 195o? Should it say right on it?

And when you said...

"The brass thing sicking out of the front of the manifold with 2 terminals in the water temp sender to the ECU."

Did you mean ("in" the water temp sender) or "is" the water temp sender?

Sorry for all the questions, I've never really worked on cars before and need to get this figured out on my own. Thanks again!

ICM (idle control module) is more properly referred to as ICS- Idle control servo. These are a common problem on Montero's . They do not send a code so there's no clear indication it's bad,,just the symptoms , advice on here and info in the FAQs section.
and sorry , I'm a bad typer and worse editor,,,I meant "is".
Depending on wether or not you have AC , an AT or MT , there are 1 to 3 brass senders on the front of the intake manifold.
Thermostats are cheap- $10- 12 bucks. If you don't know how old the one in there is , buy a new one anyway. I always change mine every 2 years right before my emmision test. Replacing them is regular maintenance type thing anyway.
We all here welcome questions, there are no dumb ones. I and alot of other folks got alot of our "Learning" right here on the Wire.
As you learn the terms and how to navigate this site you will find much info in the FAQs section, enjoy,,untill then keep on asking. <img src="/forums/images/graemlins/cheers.gif" alt="" />.

My Raider is still idling at around 1800rpms. I've replaced the Throttle Body and that didn't do anything. The IAC has been replaced, and the ICM as well. All vacuum lines have been replaced and I also check out the EGR Tube, seems to be good. I'm going to replace the thermostat and the water temp sending unit to see if that does it.

Is there anything else you guys think might be causing the high idle?

Also, I ran it in idle for 5 minutes then turn it off for 10 seconds and started it for another 5 minutes...did this about 3 or 4 times and thought I was making progress but then all of a sudden I'm back to 1800 RPMS....had it down to 1150.

Please help!

replace the temp sensor and the thermostat and report back. If that does not do the tric maybe we need to look for a vacuum leak.