Erratic starting

[1bogis]

My 944 S2 has always started Ok without any RH foot applied. Today started fine. It restarted Ok after short trip. i then drove approx 3/4 hour down M3 and parked. Came back 15mins later and although turning over OK it would not start without RH foot or with. Left it about an hour then returned. Still nothing doing. Got the AA man out and 1/2 hour later it started first time in front of him. When switched off it would not restart. AA man checked for spark, OK, restarted OK again. But still seems erractic as to whether it will or will not start. Engine runs fine when going, no erractic revs nor misfire. Any ideas please?

 

[bmnelsc]

Probably DME relay not allowing fuel to flow at startup intermittently - try your spare or the jumper you carry in the glove box (apparently we all should have a spare DME relay or a jumper wire to replace the relay for these emergencies - I don't them either so fingers crossed).

 

[robwright]

Imobiliser, fuel pressure regualtor and DME temperature sensor are all known culprits also.

 

[colin944]

Mine has started doing this after i fitted the promax chip. It wont start when its warm. Its like its not getting fuel through, you need huge boot fulls of throttle then it catches what feels like one cylinder at a time then bursts into life and runs like a swiss watch.. What could that be?

 

[zcacogp]

Mine has started doing this after i fitted the promax chip. It wont start when its warm. Its like its not getting fuel through, you need huge boot fulls of throttle then it catches what feels like one cylinder at a time then bursts into life and runs like a swiss watch.. What could that be?

Dunno, but mine is the same. With the Promax chip too.

 

[colin944]

That's interesting that you have the same problem Oli. I'm going to phone Andy at promax and see what he thinks. I'm sure he has a sign on on here so maybe he'll come on and chat with us.

 

[Frenchy]

The DME temp sensor usually lets the car run fine until warm,it then plays up telling the DME it is still cold the car over fuels and drives like a pig, it will also cut out and will not want to start until cold.

 

[colin944]

Once it starts Frenchy it runs like a swiss watch no problems at all.

 

[Frenchy]

I would discount temp sensor, possibly FPR, see if you can lend one to try, only a couple of minutes to fit, check ignition also, rotor arm and dizzy cap, the coil may also be causing this.
My last erratic running episode was down to the ECU, I suspect dry joints but I have not had a good look at it, luckily I bought a secondhand one few years ago, I will possibly send the faulty one to Augment if I cannot sort it as they are bringing big money and would be a shame to bin it.

 

[zcacogp]

I think I changed the FPR on my S2 about 3 or 4 years ago. It was certainly something on the fuel rail under the bonnet, and it didn't affect the starting problem at all. (I changed it as the CO was high, and a faulty FPR was one possible culprit.)


Oli.