Idle too high !

[Speedkan]

Hello, my car is a 2001 996 TT and it has been fine since 1 week ago when i have noticed the strange behavior of the engine at idle.

Usually it stays around 780-800 RPM but now it has raised to 1100 RPM (it's so high that it doesn't allow me to check the oil level with the computer) ... but i must say that the car runs perfectly to the red line.

I add some informations that may help to solve this problem ... the car has remained in the box for 2-3 months with the same fuel and, for this reason, i was thinking that maybe the fuel could have lost some octanes, so i have put new gasoline but no changes at all.

Second, the idle is high only with tha A/C off but if i put the A/C on it goes to 800 RPM !

Ideas ?

I have read of tech injectors cleaner ot that it's time to clean the throttle body ... what do you think ?

Thank you

[Loren]

Besides cleaning the throttle body look for loose or damaged hoses on the intake.

If you have a fault code reader verify that there are no pending fault codes.

[Speedkan]

Besides cleaning the throttle body look for loose or damaged hoses on the intake.

If you have a fault code reader verify that there are no pending fault codes.

Well. i have checked for loose or damaged hoses and they look ok but i have noticed another strange thing.

Now, without any reasons idle looks to be ok but, if the engine stays running at idle for more then 3-4 minutes i have PSM and ABS check light.

I have to switch off the car and then start again to have them reset ... and this happens everytime the engine runs at idle for 3-4 minutes.

When i start the engine, after this has happened, idle has some problems in normalising and in few seconds it becomes normal !!

What could it be ? <_<

[phillipj]

Like Loren said you have to check for fault codes or no one can help you.

[Speedkan]

Like Loren said you have to check for fault codes or no one can help you.

I know, but no fault codes ! :huh:

[wross996TT]

I know, but no fault codes ! :huh:

What code reader are you using...if you got lights on the dash the codes should be stored in the DME. Use PIWIS, PST2 or Durametric.

It could be fuel related...when was your last plugs/coil pack change?

[Speedkan]

I know, but no fault codes ! :huh:

What code reader are you using...if you got lights on the dash the codes should be stored in the DME. Use PIWIS, PST2 or Durametric.

It could be fuel related...when was your last plugs/coil pack change?

I don't know if can be compared to a Durametric but i use my R-9000 multigauge or the Nitrod.

My last plugs change was just 13000 miles ago but never made a coil pack change (and the car has 70000 miles on it).

[wross996TT]

I don't know if can be compared to a Durametric but i use my R-9000 multigauge or the Nitrod.

My last plugs change was just 13000 miles ago but never made a coil pack change (and the car has 70000 miles on it).

That code reader will not suffice...get a Porsche reader (see my list)...otherwise we are just guessing.

[Speedkan]

I don't know if can be compared to a Durametric but i use my R-9000 multigauge or the Nitrod.

My last plugs change was just 13000 miles ago but never made a coil pack change (and the car has 70000 miles on it).

That code reader will not suffice...get a Porsche reader (see my list)...otherwise we are just guessing.

Ok, good to know it ... thank you !