IDLE HELP!
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FTO338
- Oldtimer
- Posts: 6712
- jedwabna poszewka promocja
- Joined: Sun Feb 09, 2003 6:00 pm
- Location: Port Melbourne: Pimping with RX400h, B200 Turbo.
Well under normal condition, when the car starts up it should be around 1200rpm during idle, cause its cold, after 5-10mins of warm up it should be around 720rpm. Once u got it on the road & say drove around for 5mins, it should then idle around 650-720rpm. Then again it all depends on the mod u did 2 your car!!
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GPXXX
- Oldtimer
- Posts: 3433
- Joined: Sat Apr 12, 2003 5:00 pm
- Location: < the matrix >
also worth noting is that if the problem persists after swapping to a beefier battery, it could be a problem with the compression loss... i had similar idling problems on my old shitbox lancer once and it was traced to a cylinder that was losing compression due to faulty spark plugs...
either that or the previous owner might have replaced the camshafts with a lumpier item (which i highly doubt since you reckon the car is stock std).
hope all goes well for you...
edit: my Lancer was a shitbox, so that's just an exception...
either that or the previous owner might have replaced the camshafts with a lumpier item (which i highly doubt since you reckon the car is stock std).
hope all goes well for you...
edit: my Lancer was a shitbox, so that's just an exception...
Last edited by GPXXX on Wed Jun 11, 2003 1:13 pm, edited 1 time in total.
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G1
- Mechanic
- Posts: 728
- Joined: Sun Aug 04, 2002 5:00 pm
- Location: VW Bora V6 4Motion
- Contact:
you might offend some lancer owners out there 
there was an FTO for Dummies web site which had info on idling problems, but it seems to be down.
From mivec.co.uk
Q. My car is lumpy and/or cuts out at idle (or I have a faulty Idle Speed Controller)
A. [This courtesy of Adrian Wright] The ISC (Idle Speed Controller) is a small stepper motor, capable of moving up to 120 steps, bolted to the side of the throttle body. It controls the opening and closing of the idle butterfly, which obviously should open when the engine is cold, and close completely when warm and under normal load (it will open if the engine is loaded, with either heavy alternator load or aircon, etc.). It's normally the cause of idling problems.
Problems (1) : The 120 steps appears to be a notional figure rather than an actual - ie 0 is not closed and 120 fully open. Depending on the car, how it was serviced and whether this 'steps' figure has been reset, many FTOs typically have around the 40 'steps' mark as fully closed. Problems can arise when the fully closed 'steps' gets too high, as the ECU will only step up to 120 max. Therefore if the fully closed number of steps is, say, 80 you only have 40 steps until max - which will only partially open the idle butterfly and hence the car will not idle when very cold or under very heavy load. Apparently a Mitsi service should reset this (steps figure to a lower value), providing they've got the kit to do it.
Problems (2) : The ISC gets covered in black carbon deposits which prevents it working properly - typically causing hunting at idle and general eratic idling. Remove it (two bolts hold it to the throttle body) clean the hell out of it (WD40 or something), clean the hole in the throttle body where it fits and finally clean and lubricate the main throttle butterfly and interior of the throttle body just for good measure.
Problems (3) : The ECU needs to 'learn' where the idle point is - so an ECU reset can sometimes help to force it to relearn!
Problems (4) : Due to the position of the ISC and the wiring loom, the wires to the ISC are prone to fracture and complete breakage. Simply pulling back the black plastic looming material on the six wire connector should show whether all wires are in fine fettle. If you doubt the continuity of the wires, the Owners Club have the Electrical manual and it's not TOO difficult to trace all 6 wires on the connector back to the 1st ECU connector and one of the junction blocks, both in the passenger footwell.
Problems (5) : Low idling, but everything else is OK - just need to pump up the idle. The throttle body has a recessed idle screw, on the top - towards the front, normally covered by a very obvious circular black rubber dust cap (about half an inch in diameter). Simply remove the dust cap, and turn the screw in or out to increase or decrease the idle speed.
there was an FTO for Dummies web site which had info on idling problems, but it seems to be down.
From mivec.co.uk
Q. My car is lumpy and/or cuts out at idle (or I have a faulty Idle Speed Controller)
A. [This courtesy of Adrian Wright] The ISC (Idle Speed Controller) is a small stepper motor, capable of moving up to 120 steps, bolted to the side of the throttle body. It controls the opening and closing of the idle butterfly, which obviously should open when the engine is cold, and close completely when warm and under normal load (it will open if the engine is loaded, with either heavy alternator load or aircon, etc.). It's normally the cause of idling problems.
Problems (1) : The 120 steps appears to be a notional figure rather than an actual - ie 0 is not closed and 120 fully open. Depending on the car, how it was serviced and whether this 'steps' figure has been reset, many FTOs typically have around the 40 'steps' mark as fully closed. Problems can arise when the fully closed 'steps' gets too high, as the ECU will only step up to 120 max. Therefore if the fully closed number of steps is, say, 80 you only have 40 steps until max - which will only partially open the idle butterfly and hence the car will not idle when very cold or under very heavy load. Apparently a Mitsi service should reset this (steps figure to a lower value), providing they've got the kit to do it.
Problems (2) : The ISC gets covered in black carbon deposits which prevents it working properly - typically causing hunting at idle and general eratic idling. Remove it (two bolts hold it to the throttle body) clean the hell out of it (WD40 or something), clean the hole in the throttle body where it fits and finally clean and lubricate the main throttle butterfly and interior of the throttle body just for good measure.
Problems (3) : The ECU needs to 'learn' where the idle point is - so an ECU reset can sometimes help to force it to relearn!
Problems (4) : Due to the position of the ISC and the wiring loom, the wires to the ISC are prone to fracture and complete breakage. Simply pulling back the black plastic looming material on the six wire connector should show whether all wires are in fine fettle. If you doubt the continuity of the wires, the Owners Club have the Electrical manual and it's not TOO difficult to trace all 6 wires on the connector back to the 1st ECU connector and one of the junction blocks, both in the passenger footwell.
Problems (5) : Low idling, but everything else is OK - just need to pump up the idle. The throttle body has a recessed idle screw, on the top - towards the front, normally covered by a very obvious circular black rubber dust cap (about half an inch in diameter). Simply remove the dust cap, and turn the screw in or out to increase or decrease the idle speed.
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EXC
- Apprentice
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YYgirl
- Grease Monkey
- Posts: 184
- Joined: Thu Mar 20, 2003 6:00 pm
- Location: Brisbane
maybe you need to replace the stepper motor. hehe that's what everyone told me to do. Maybe first reset the computer, by disconnecting the battery for 30 min.
My car idles a bit better now, i just made it idle higher by adjusting one of the screws on stepper motor, its all fine now i think.
However, I have replaced the stepper motor, bought one at import car shop, I have changed the spark plugs, and cleaned out the carbon that had been deposited in the stepper motor.
Hope I'm not wrong, but when you turn on the air-con, it's suppose to idle higher.
My car idles a bit better now, i just made it idle higher by adjusting one of the screws on stepper motor, its all fine now i think.
However, I have replaced the stepper motor, bought one at import car shop, I have changed the spark plugs, and cleaned out the carbon that had been deposited in the stepper motor.
Hope I'm not wrong, but when you turn on the air-con, it's suppose to idle higher.
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fredcdn
- Newbie
- Posts: 6
- Joined: Fri Feb 14, 2003 6:00 pm
- Location: Brisbane
How much did you pay for your ISC? I have been quoted $250 from Nardek http://www.nardek.com.au and this seems way too expensive.
I'm going to ring Mitsubishi and some other parts places because the one from my Mirage is exactly the same (as stated on Nardek's website) and it seems to idle a lot better - although a bit high sometimes.
After pulling the ISC apart and putting it back together (I know which coil is broken/damaged) it was fixed for a day or two but back to the same problem now.
I found these (non-FTO) sites usefull since they have exactly the same ISC info.
http://dmtalon.v8eaters.com/ISC.html
http://www.dsm.org/how-tos/tttt/tttt3.html
I'm going to ring Mitsubishi and some other parts places because the one from my Mirage is exactly the same (as stated on Nardek's website) and it seems to idle a lot better - although a bit high sometimes.
After pulling the ISC apart and putting it back together (I know which coil is broken/damaged) it was fixed for a day or two but back to the same problem now.
I found these (non-FTO) sites usefull since they have exactly the same ISC info.
http://dmtalon.v8eaters.com/ISC.html
http://www.dsm.org/how-tos/tttt/tttt3.html