maverick

My car has developed a problem. On start up she runs very rough/lumpy and has a very bad lope. RPM is barley off the rest and dies a lot. If you give her gas it will run up then stumble. She smells like she is running very rich. I can get her going on the road but throttle response is off. Any ideas?
Thanks

964TURBOCHAS

this happened to my C4 years ago

New plugs and wires was my solution

Metal Guru

If the idle has changed check the oil cap. If it isn't sealing it will be puking oil out.
If it is allowing air to be pulled into the crankcase the air eventually ends up in the intake track and acts like an intake leak because it is essentially un-metered air.

911addict

Cheap fix to check first: air blockage. Have you had the filter off recently? Either foreign matter or o-ring etc. not refitted correctly

Ag02M5

Sounds like vacuum leak. Had that issue a couple times and those exact symptoms. Once was unseated intercooler and the other was the AAR hose had come loose.

RT

maverick

Thanks for the input I will check these things. Another point of reference is that after a while of nursing the idle returns to normal. But after shut down the problem reoccurs.
I haven't touched the airfilter in a while I am running the stock air box with a K&N filter element. Similarly the intercooler hasn't been disturbed. The car sits for long periods without moving( I know string me up!) Where/what is the AAR hose? Do these cars have a sensor for air fuel mixture?

Metal Guru

The 964 T has a narrow-band O2 sensor.
Try an "Italian Tune up"; one to two runs to the red line and see if that clears your plugs up.
When was the last tank of gas put in. Summer blend fuel will go bad after a period of time and cause plug fouling and rough running.

maverick

Paul,
I filled it up about 3 weeks ago and took it to a performance driving school. It was a bit rough to start from home then ran OK. But at the track when I would start it up it ran rough very rich smell and wouldn't stay running with out throttle modulation. Then it would seem to clear up and run fine until I shut it down again. Probably need to take it to the Dr just thought id see if it was a simple fix:-) always worth a shot with all the brain power and school of hard knocks experience out there!

jeff91C2T

Hey Paul...something else (easy) you might try is unplugging the O2 sensor. The connector is on the drivers side of the engine bay and easy to find. This should rule out it's the sensor...

Gandara

Took mine to the shop for the same symptoms today, see what happens.