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Big_Fat_N_Black
02-19-2003, 01:24 AM
My car has descided to start idiling all crazy like! Some times it runs just fine the out of the blue when i clutch in to shift the RPM will jump up. Under load it settles down but at stops with it clutch in or out of gear they rev way high usually for a min or so then drop back down to normal. Also when this is happening... If i shut the car down and try to restart it, It wont start easily. It will turn over nicely and after a bit will sound like its going to fire up but will die. I have to have the pedal right to the floor and keep it turning over for a good 10 seconds or so before it will roar back to life with a grey puff and the smell of excess gas.

Are these the symtoms of any sensor in paticular failing...
It looks like my coolant temp sensor may be bad cuz my fan isnt coming on... could this be a possible cause...

Thanks
CeD

Joisey Jim
02-19-2003, 03:58 PM
CeD - I have a couple of thoughts here - 1. If your temp. sensor is not letting the EEC know that you are warmed-up, then you might stay on a higher (warm-up) idle & run rich (gas smell could be an indicator) 2. My best guess, however, would be the IAC or IAB on the throttle body - this regulates the idle by by-passing the throttle plate & is famous for sticking with age. You can try a quick cleaning with an intake safe spray cleaner by shooting it thru the passageway (inside the throttle body) or better still remove the plastic IAC valve body itself and lightly brush or spray clean the dust/crud off the plastic bellows inside. It's fairly easy to remove, 2 small hex head bolts I recall. If cleaning improves it initially but it reverts back to a high idle then I'd replace the IAC. Also this cold weather I would disconnect the negative battery cable and don't try to remove the IAC electrical connector - they are very prone to breaking. There should be enough cable slack to turn it over for cleaning. If you have a K&N air filter I would also clean the MAF wires with a q-tip & alcohol, as these are prone to getting oily from the filter & causing some idle irregularities
Good Luck.

Big_Fat_N_Black
02-19-2003, 06:55 PM
sounds easy enought, worth giving a try. But Im really thinking its computer related as it seems to be not just sticking at a higher rpm but instead jumping to a high rpm (25000+).
Also now, in getting a check engine light and even when its not idling all crazy it lags on me on acceleration....

Your ideas are greatly appreciated!!!

CeD:confused:

Joisey Jim
02-20-2003, 04:32 PM
If it were just the tack jumping/swinging up to 2,500rpm then I would say it's the cam sensor. But if the engine actually does this then I have to believe it's throttle body or MAF related. Bad DIS modules tend to cause bucking & missing. I don't know what your mech. skills but you need to extract the 'check engine' codes - that will give you some direction as to what sensor is out of range. It could also be the second sensor on the throttle body - the TPS which senses the actual throttle position. These can also be tested & if necessary, rotated a little to bring it back into spec. So you need to download the codes & have you done any work at all recently on the TB or MAF.
Jim.