Engine will only tick-over

[Trackrod996]

Sorry to repeat myself but I'm getting very concerned as engine fires up OK but will only tick-over, irrespective of throttle action. Ambles up to around 1500 revs and that's it. Seems reasonable to suspect it's to do with the fly-by-wire throttle, but what? Only happened after leaving the car for 3-4 weeks and prior to that absolutely no problems.

 

[Richard_Hamilton]

You really need to get a diagnostic check done with a Porsche tester. It could be either the throttle potentiometer on the pedal, or the actuator on the throttle body. Or it could be a fault in the DME module itself, MAF, or other sensor. Without a diagnostic test you would be shooting in the dark, unfortunately. Sorry I can't give you a definite answer, or a simple solution, but I don't think there is an obvious one, other than looking around the engine compartment for something that has become disconnected.

 

[Trackrod996]

I had the Porsche man around a week ago, who plugged in the magic box and came up with 'fault 402 / e-gas throttle valve position error'. He wasn't able to do anything on the day, and due to the lousy weather I was none too bothered. However, he came again today, and checked again before removing the unit, only to find no fault! Car starts just fine, and I've been out this afternoon and the old girl runs like a bird. My only concern is that it is an intermittent fault, but at least I know what it is. Why it suddenly came, then went is a mystery, but at least Goodwood tomorrow, weather permitting, looks like a go-er.