944 Refusing to start - UPDATED

lofi · **Posted:** Thu Jun 18, 2015 6:24 am

Pink piggy wrote:

frenchy wrote:

Had a faulty ECU temp sensor ,fine when cold but because the sensor was faulty the ECU thought the car was still cold when it was warm and kept pumping fuel in hence no run.

Was the temp sensor on the coolant or was it inside the ECU?

Yes I really dont understand much about electrics :oops:

It's the sensor on the engine - new one arrived and looks like this

IMG_2673 by pierslofi, on Flickr

lofi · **Posted:** Thu Jun 18, 2015 6:27 am

frenchy wrote:

Had a faulty ECU temp sensor ,fine when cold but because the sensor was faulty the ECU thought the car was still cold when it was warm and kept pumping fuel in hence no run.

My symptom is that it doesn't run the fuel pump at all. Not convinced the new sensor will do the job but it's a cheap thing to cross off the list, and the diagnosis does point to it.

lofi · **Posted:** Sat Jun 20, 2015 2:22 pm

Changed the sensor still doesn't go. Did for a bit with the sensor unplugged.. Runs fine with live direct to fuel pump. Bum

Pink piggy · **Posted:** Sat Jun 20, 2015 5:00 pm

lofi wrote:

Pink piggy wrote:

frenchy wrote:

Had a faulty ECU temp sensor ,fine when cold but because the sensor was faulty the ECU thought the car was still cold when it was warm and kept pumping fuel in hence no run.

Was the temp sensor on the coolant or was it inside the ECU?

Yes I really dont understand much about electrics :oops:

It's the sensor on the engine - new one arrived and looks like this

IMG_2673 by pierslofi, on Flickr

Thanks for this its a good place to start with my car sometimes will not start when hot.

Waylander · **Posted:** Sat Jun 20, 2015 5:10 pm

If it's a pain to start when hot, the normal culprit is the non return valve on the end of the fuel pump

Without pressure the fuel boils in the injectors and vaporises and the car won't start

lofi · **Posted:** Sat Jun 20, 2015 5:53 pm

Waylander wrote:

If it's a pain to start when hot, the normal culprit is the non return valve on the end of the fuel pump

Without pressure the fuel boils in the injectors and vaporises and the car won't start

Is that part of the pump or an external valve? Just learning . . . .. . . . :oops:

Waylander · **Posted:** Sat Jun 20, 2015 9:48 pm

In the end of the pump but removable

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944 Refusing to start - UPDATED

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