Cuts out when initially started

[Guest]

Hi all,

Just getting to grips with my 964. Quick question, when I start the car I need to keep a slight foot on the gas to keep it from cutting out in the morning until I get going. Also, if I have been driving it and then stop th engine... and then start the engine again abut 10 or 15 minutes later same thing! When it's going though it idles lovely at traffic lights even after 2 minutes.

Is there a choke I am missing or something like that?

Thanks,
Adrian

 

[Dave Wilkinson]

Adrian,

There is no "choke" as such - the cold start fuelling is handled by the DME in response to sensors like the cylinder head temperature and air flow sensor.

Your cold running problem sounds a little like there is an issue with the cylinder head temperature sensor. When the engine is cold the DME should raise the tickover speed until the CHT sensor indicates that the engine is warm. If the CHT sensor fails it's likely to think that the engine is warm already and not raise the tickover.

I suspect a "Hammer" test at an OPC or indie might confirm this.

Regards

Dave

 

[Guest]

"I suspect a "Hammer" test at an OPC or indie might confirm this. "

Pardon my ignorance... but what is a Hammer test?!

 

[Steve Brookes]

It's an older version of a Porsche computer for diagnosing the system.

 

[ravva]

Can confirm the above. Had precisely the same problem with my 91 C4 and its now fine after having gone under the hammer during recent northway service. it may be simple as the hammer re-setting the DME to re-calibrate the settings rather than a failed sensor per se.

 

[Guest]

thanks all, great forums here.