Idle

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 7:06 pm

OK, my first real car problem. Ive done some research on here, and previous posts seem to indicate a stepper motor fault, but I just want to clarify, and maybe get opinions on the best way to confirm the diagnosis.

Todays Events:
The car has been running fine, no idle problems what so ever, in the past. I had 3/4 a tank of fuel, but being cheap day, I topped up anyway. from the same servo I always go to, using BP Ultimate. Car was still running fine when I left there. I live 2 mins up the road, and as I pulled into my driveway, the car stalled when I pushed the clutch in. First time EVER. Anyway, Now I start the car again and it will not idle. If I hold my foot on the throttle, it sounds fine, but as soon as I remove it the revs drop and it stalls.

Advice from all the mechanically minded on here is greatly appreciated. Can the stepper motor fail so quickly ? or is there usually some form of degradation first ? What else could it be ?

Thanx in advance.

Post by **Bennoz** » Tue Aug 29, 2006 7:09 pm

Sounds similar to an issue I had (which was the stepper.)

Can you tell me if the thermo fans are on when it happens?

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 7:27 pm

When I first got home, and I tried restarting the car, I noticed the thermo fans were spinning up, then stopping when the car stalled. I just tried again just now, and the car has been off for just over two hours, so its a fair bit cooler, and the thermo fans did NOT spin up.

Post by **Bennoz** » Tue Aug 29, 2006 7:30 pm

Sorry, I didnt explain myself to well. If the car is just sitting there with the thermo fans off, idling, does the problem happen?

The problem I keep seeing is when the car is warm at idle (idling properly) and then the thermo fans come on, the idle then goes to sh*t & it can stall.

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 7:36 pm

Ahh. Well, like I said, it's still stalling and the engine is fairly cool. I cant get it to idle at all atm.

Turn the key, starts, revs drop, stall. Thats all its doing. So I guess the answer to your question is that it still stalls without the thermo fans.

Post by **Bennoz** » Tue Aug 29, 2006 7:44 pm

Ah ok. Well you can test the stepper to see if thats the problem

http://lightning.prohosting.com/~v8mate/mitsux.html

But if you are anything like me "Electronically Challenged" - Take it down to your local Mitsi & get 'em to hook it into the Matrix to diagnose it for sure.

Just dont ask for the cost of a replacement from them...

*cough *290!* cough*

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 7:52 pm

Well, being an electronics technician, I think that test is within my scope LOL.

Guess ill pull it out and test it then

Thanx for the info, and i'll let you know how I go.

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 8:33 pm

Checked the coils as per the website you sent (which says the same as the FTO manual oddly enough) and they check out ok... Any other ideas ?

Post by **Bennoz** » Tue Aug 29, 2006 8:36 pm

TPS would be the other thing that comes to mind
(Throttle Position sensor)

http://www.ftooc.org/phpbb/viewtopic.php?t=45401

onnzo · Post by **onnzo** » Tue Aug 29, 2006 8:49 pm

Check your ecu for error codes.

Check the wiring to the stepper motor (as per the manual)

Also check your afm plug if you drive a gr and the map sensor hoses if yours is a gpx.

Mike

Post by **Bennoz** » Tue Aug 29, 2006 8:54 pm

onnzo wrote:Check your ecu for error codes.

Good point... its always the simple things I forget!

http://www.ftowa.com/html/workshop/workshopart07.html

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 9:07 pm

OK, That's odd.

I had to remove the battery to access the stepper motor with the multimeter leads. Disconnected for about an hour cos I stopped for dinner. Well, I plugged the stepper motor plug back in, replaced tjhe battery, and reassembled everything. Started the car to check it was still stuffed, but to my surprise, it started, and has now been idling for about 5 minutes. ??? WTF ??

Could the stepper Motor plug have maybe worked loose and just required reseating ? It was rather easy to get off the first time, and i noticed a "click" when i put it back on...

Ill keep a close eye on things though. Did disconnecting the battery effect the ECU or something maybe ?

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 9:19 pm

OK, Disregard my last

It idled for a while, but the longer I left it the lower the idle. I took it for a drive, and when I came back its back to not idling at all again. I suppose it could be temp related ?

I'll check for ECU errors.

Sparhawk · Post by **Sparhawk** » Tue Aug 29, 2006 9:47 pm

OK, checked ECU for errors. None.

Post by **Bennoz** » Tue Aug 29, 2006 9:57 pm

Sparhawk wrote:OK, checked ECU for errors. None.

Possibly because you just disconnected the battery, you have just reset the ECU & cleared the codes. Get the problem to happen for a while longer & recheck the codes.

umm · Post by **umm** » Tue Aug 29, 2006 11:03 pm

This is the same problem i had and still kinda have. It was caused by my tps and gunk in my intake and a bit because of the stepper.

Getting another tps solved the stalling problem...well mostly, it still done it but very rarely and it had very crap idle and bouncing revs at low rpm.

When i last had the intake off i noticed it was full of gunk, so i gave it and all around the butterfly and stepper a good clean with so $9 stuff from super cheap called Nulon throttle body and carby cleaner. It works great an i just sprayed it in an it dissolves all the crap.

That solved pretty much everything, it now idles better and hasn't stalled since and that was a few months ago.

I still have a bit of an idle problem though, but barely noticable and is because my stepper is pretty much dead...but still works so i'll leave it until it fully dies

Anyway i'd suggest this:
Check and adjust TPS
Clean Intake and throttle body
Clean stepper

Also a quick fix that let me drive around until i fixed it was to adjust the idle screw to give you a bit of revs so it doesn't die when you start it or at traffic lights.

umm · Post by **umm** » Tue Aug 29, 2006 11:05 pm

Also when mine was stalling i didn't get any error codes.

Sparhawk · Post by **Sparhawk** » Wed Aug 30, 2006 6:20 pm

OK, a day later and Ive tried again.

I checked the stepper motor and throttle body, and they look clean, so didnt bother getting any cleaning agent YET...

First try for the day - stalled. Same as yesterday, and the engine was cold.

Reset the ECU (disconnected battery) - Started ok, Idled for 10 minutes according to the manual and the revs slowly dropped, and after 10 mins was at about 400rpm. Stopped and restarted, still idling low. Gunned engine a few times, and then back to stalling.

Reset ECU again - This time because the engine was already hot, so hopefully the idle time was under stable conditions. Idled OK after initial start at around 600rpm. Ran it for a further 10 mins, and it seemed to drop a little, maybe to 500, but still not too bad.

Stopped and restarted and it seems to be back to normal. ie start with no throttle revs to about 1.5 and slowly falls back to about 900rpm. Idling ok, drops a little when thermo's cut in and out, but adjusts accordingly. Switch on the Climate Control, and the revs drop to around 500, but adjusts back to a stable 8-900. So it seems normal to me.

Next step is to let the car cool down, and try again I guess...

Will keep you posted...

Sparhawk · Post by **Sparhawk** » Fri Sep 01, 2006 11:29 am

Well, time for an update;

I drove the car to work yesterday, and it was fine. not a problem, drivibg how it always has. On the way home from work though, 5 mins down the road, it stalled when I pulled up at an intersection, and played up all the way home.

Pulled things apart again to have another look.

umm wrote:Anyway i'd suggest this:
Check and adjust TPS
Clean Intake and throttle body
Clean stepper

Did these. TPS OK, Removed and cleaned Stepper motor, and cleaned Intake and throttle body with the same stuff you used (but it cost me $11 instead of $9

)

Put everything back together, and it started and idled, albiet a little lower than normal.

Started it up this morning, and was idling ok. Did the usual 5 min warm up before driving to work, and it didnt stall, but was still idling a little on the low side. On the way to work it started stalling again.

Once I got to work, it stalled when I pulled up, but I kicked it over 5 or 6 times, and eventually it stopped stalling, but revving very low (400ish), and if I turn on the climate control, the revs drop to almost stall before it picks up.

So Im a little confused as to what the cause could be. Could it be a wiring problem to the stepper (if so, how do i check it) or could it be a bad batch of fuel, cos it started happening right after i filled up ? or could the stepper motor be intermittent ? Anything else ?

onnzo · Post by **onnzo** » Sat Sep 02, 2006 4:46 pm

Check the wires to the stepper motor. Mine wouldnt idle when cold for 5 years. Ended up finding that one of the wires to power the steppers coil was broken!

Another forum member also had this problem.