OK, major issues with stalling today, I don't seem to have any idle at all. From reading around, this would appear to be something to do with the ICS Motor, and apparently it would cost me about $400 - $450 to replace this, when I'm not even too sure whether it's actually faulty or not.
Basically, when I would be any situation were you are normally operating on idle (eg. braking into a corner, sitting at lights, etc), revs would just go to nothing - it's not attempting to keep an idle speed at all.
The RACQ guy came, said something about having a manual idle override, twiddled some things, and I had an idle of about 2000rpm until I got home, when it promptly forgot about any tweaking and went back the way it was.
Any ideas? And any tweaks I can do to at least make it driveable for the moment?

An article I read said something about listening for the ICS Motor operation. I usually get some sort of short buzzing/whining motor sound when I start up, which I had thought was something to do with the power steering, but now I'm not getting it most of the time, and when I do it still doesn't idle?

Any tips would be GREATLY appreciated, as I can't really afford to get anything fixed at the moment!

PS. Ironically, I just bought the Hayes service manual yesterday. Didn't have it with me today though, and when I DID get to look at it, it hasn't proven very useful. All very vague about things...

ICS Motor is available for around $105 from Bursons (non genuine) and takes about 10mins to fit with just a screwdriver and a small socket driver. Maybe yours either needs a clean or replacement.

when you turn the ignition to on (not start) and off again you will hear the isc motor it's easier with 2 people and with the bonnet up to confirm it's working. It will also make noise if the computer gets a crank angle signal.

Bursons have always been good value (I used to shop there), pity there only in Victoria

i had my ICS Motor disconnected for a week or so and when it idled it just sat on 1000 rpms didnt use much more fuel... it got accidently knocked off while changing something and i thought it might of been then ecu just running in cause i reset it cause my battery was playing up at the time. Thats on a v6 though... 4 cyl would be different im guessing....

Yesterday I did some messing around, unplugged the ISC, plugged it back in, etc., and now it seems to be working fine? (PS. it was raining the day I had the problems)

HOWEVER, when I tried running the car with the ISC unplugged (6cyl, BTW), I get no base idle. From reading the reply posts, sounds like I SHOULD have an idle of some sort without it.
So I am wondering how the idle screw (I'm guessing it's the golden screw below the throttle turny bit?? - only shows the 4cyl version in my service manual) and the ISC interact - ie., if I disconnect the ISC, can I turn the idle screw until I can maintain an idle without it, then reconnect, and have it work properly, or will this throw the ISC out? I figure that way if I suddenly lose the ISC, I'll at least have a constant idle speed that won't kill my engine every time I take my foot off the accelerator?
If the idle adjust is the screw I'm thinking it is, I think mine looks like it's been wound right back?

dont know if this is any help but.... when i first bought my KS it had a habit of stalling and not holding an idle at really awkward times, i took it to where i bought it where they promptly diagnosed IDSC motor after having that replaced not a prob at all... idles beautifully

dont know if this would be any help, but my tn was stalling because the mechanic forgot to connect the Oxygen sensor lead.

a good way to check if your ISC is actually working is to turn on the air-con at idle, if the revs rise you know its working :P

worked for my diagnosis anyways

if you need 1, go to ebay, i saw portside mitsu selling them for like $79 ea, btw it's under mitsu parts, and i have no affiliation whatsoever with the seller, just want to inform you a good deal :D

OK, this is really weird, the problem came back today, so I've been trying to figure out what the f@#k is happening, and it all seems to be very intermitent. I've been going on the theory that there's somethig amiss with the ISC Motor, but I don't know now that that's the case.
Sometimes when I disconnect the ISC, the revs just drop and it dies, ie. no idle. But other times, it sticks to mybe 700rpm. Which leaves me wondering if it does actually have anything to do with the ISC, 'cause it seems to give varying results without it!
Just so everyone knows what the setup is, it's a fuel-injected v6, manual transmission (which means I can't just keep one foot on the accelerator at all times just in case)
Seems possibly like it's doing it more when it's warmed up.

I guess I might just have to give in and take it to the mitsubishi service centre. Am NOT looking forward to the bill. IF it does need a new ISC motor, I wonder if they'll let you supply one from elsewhere? (the genuine part was quoted as about $360, as opposed to $80 for non-genuine...)

before taking it to mitsubishi, get yourself a brand new ISC motor, not from Mitsubishi. Should be in the area of $100 which really isnt a big deal. If it doesnt solve the problem, then at least you've got a brand new ISC motor that you wont need to worry about in the long run.

The proper way in testing the ISC motor is not by unplugging it, but by covering the vacuum holes inside the throttle body. Reason for this is the ISC motor might actually adjust itself freely if it doesnt receive power, which may be the reasoning behind your results.

Well, got it fixed by Ultratune (Indooroopilly) today, apparently the ISC Motor was fried. $270 all up, including checking a few other things. Not something I'd like to pay for every day, but I needed it professionaly diagnosed quickly, and Mitsubishi were going to charge about $400+ for the same thing. If it wasn't an issue to have it off the road for a while, I could have got the motor cheaper (cost $167, Mitsu quoted about $335), but I needed to travel over 1000kms this weekend, so...

One thing the Ultratune guy told me, which people might want to keep an eye on theirs, is that the capacitors in the ECU are known to go after about the 10yr mark, and one of the first things they affect is the idle system. Being electrolytic, when they leak they can destroy parts of the board, etc. So might be worthwhile checking your ECU caps, and replacing them if possible - should hopefully be relatively straightforwad to do, and could save you a bucket.
The guy checked mine, and they're fine, at least for the moment.

I have a post with pretty much the exact same problem. I changed the idle speed control motor but I think the mechanic used a dodgy second hand one cos the problem is still there. What I wanted to know is if the part you got was a genuine or not. Do I have to replace it with an extra-expensive part and be in debt for ten years just so I can go shopping in the darn thing each week? Is a non genuine part just as good, even short term?

The part Ultratune got was non-genuine, from Repco, think it was maybe $120 or so. Haven't had any problems since, so...

One work of warning for everyone, DO NOT TOUCH THE THROTTLE STOP SCREW there is a air screw under a little black cap on top of the TB.

This is where you can adjust the base idle, you will also need to bridge the ecu with the plug inthe engine bay, madmagna.com has the info you will need.

So that there is a final solution in the one spot:

From MadMagna.com (end of "cleaning throttle body" article)
"While cleaning disconnect battery. when all has been re assembled hold foot on acc to floor, turn ignition to on without starting and hold here for 30 seconds. this will reset isc motor.

Start car and bring up to operating temp. stop engine and bridge wire in engine bay behind left strut tower, is usually a beige one but check if unsure. this will turn off the isc. Mitsubishi states idle should be 700 in neutral but I have found it is better at around 850. Only use air screw to adjust as the throttle stop screw should never be touched. (hint, on some models this plug is in different places, fine someone who can show you the right plug and ALWAYS us a fused bridge wire)

I hope this is a help. I have done the many many times and in 95 percent of cases the you would never tell the car is running after this has been done"


OK, questions:
1. Is this (attached) the air screw mentioned for adjusting idle? (V6, don't know if it's the same for 4cyl). Can't see anything with a cap over it, so thinking this is it with the cap missing?

2. Where and how exactly do you bridge the ECU? ie. where is the wire when you are looking into the engine bay from in front of the car, can you reach it from above, how exactly do you "bridge" a wire, etc?

HI,
i don't think you have to go as far as replacng the ISC
i had the same problem with mine, the engine would just stall all the time, couldn't keep revs,
i finally figured out that it was the fuel i was using, it was causing build up on the injectors,
i ran some 98% octane and gave the engine a good hammering, and it cleaned up the injectors no dramas.
now i always run 98% every 2 or 3 tankful,
just try that and see how it goes.

I think im having a similar issue (better off leaving here than starting new thread)

Taking off around corners sometimes the revs just bottom out... and u cant hear anything...

pump it a few times ( you get a bit of a knock) then it fires up again...

would this be the ISC motor?

when i had idle troubles, it was after i disconnectd the battery. i rang mitsu service and they said the ecu was reset. they fixed it up for $50 i think it was

nodz thats excatly whats happened.. do u know what they did to it?

i think something along the lines of reset the ecu, but make sure it re-learns everything. i dropped it into them about 1pm, and it was ready by 3:30 same day. When u ring them up, tell them u had the battery disconnected

cheers for the help fuzzet... mitsubishi here i come :)

cheers for the help fuzzet... mitsubishi here i come :)
no problem. ive seen many people with the same problem that u have, and i did, but they were spending hundreds on new idle controllers etc...

I think im having a similar issue (better off leaving here than starting new thread)

Taking off around corners sometimes the revs just bottom out... and u cant hear anything...

pump it a few times ( you get a bit of a knock) then it fires up again...

would this be the ISC motor?
Sounds electrical, spark plugs? leads? alternator? distributor/cap?
I know whilst turning the power steering can take a fair bit of power out of the car if you are having troubles with the alternator.

Sounds electrical, spark plugs? leads? alternator? distributor/cap?
I know whilst turning the power steering can take a fair bit of power out of the car if you are having troubles with the alternator.

Thanks for the help :) it seems to happen when driing in a straight line also...

but i think what fuzzet said is right on the money... mitsu should be able to sort it...