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ecl
27-09-09, 12:06
had the car in for a mot while i was on vacation. They could tell me it had unusually hi co, and maybe running a bit rich. This could possibly be the watertempsensor? am i right?

then when got home and was gonna go for a drive, it had been sitting for a week or so, it just wasn't really willing. i got it started after 20-30 seconds on the starter and it jumped up to 2000 rpm and stayed there for a minute or so, while it was running at 2000 rpm i could not use the accelerator, it just overflooded or something, it just wasn't willing. then after about a minute it dropped down to usual idle at around 1000, and the car feels just fine. Seems completely normal when driving. It's only starting it that is a pain.

it has always started really easy earlier.

any pointers?

thanks

-Eivind

wrinx
27-09-09, 13:30
Revs could be the Idle Actuator sticking and then correcting itself. Water temp sensor does cause starting problems if it's giving the wrong signals...it can be tested :)

wrinx

ecl
27-09-09, 21:24
the idle control valve has just been cleaned. not many km's ago. Could it still be stuck maybe? should it be greased or oiled or something for less friction?

could any air leaks be giving me the symptoms i'm experiencing?

it started fine today, but after driving for 3 minutes it didn't seem right, stopped at the trafficlight, idle at 2500 before it died on me. Would start again a couple of minutes later though, seemed to be fine, so took it back home after getting it good and warm, it been running really well lately.

then it died again in the garage, while i was looking under the bonnet fiddling with cable to the water temp sensor, so maybe i have a connection problem? would disconnecting the water temp sensor cable make the engine stop? could it be a cable break on the water temp sensor cable make it act up? it seemed to change engine behavior when touching the cable. The engine was to hot and it was to late to start looking further into it today.

I know a lot about this car through my own experience and reading about it, but never heard of this kind of problems, so any suggestions or thoughts would be appreciated. This forum is great help.

-Eivind

wrinx
28-09-09, 07:30
The behaviour doesn't sound like IAV now. Do the test with the cable again, it is possible that's your problem :D

wrinx

SteveNZ
28-09-09, 13:04
Sounds like a typical coolant sensor fault, or maybe the wiring. Generally the resistance falls off which will mimic a cold or colder than normal engine temp. This will cause the ecu to increase the idle speed, sometimes very erratically

If its reving at 2000, just try unplugging the ICV (2 pin electrical connection). If revs fall back, the valve is working and the ecu is holding the revs up.

Try registering the coolant sensor signal on a scope or even a multimeter. As the temp rises the the sensor will draw more voltage away and the signal voltage will drop.

As a guide when cold it will be about 2.5v, when hot it will be less. If its running up around 4-5 there is a problem. Measure at the ecu rather than the sensor to test the wiring and plugs etc.

A scan tool will do the job a lot easier if you have access to one.

Of course make sure throttle cable, throttle etc is not stuck and the TPS should be checked also