Starting problem when hot - 2007 2 litre automatic 9-3 aero Sportwagen

[ibayliss]

Dear Fellow SAAB owners.

I have a very odd problem with my 2 litre Automatic 9-3 Aero Sportwagen MY 2007 76K miles.

Normally, cold or hot, the car starts first pop but sometimes when the engine is hot, it is a bit reluctant to start after, for example, re-fuelling.  Sometimes the take up on accellerating away from stop has a lag or is a bit jerky.

The throttle needs to be tickled and after the second try it starts but runs a bit lumpy. After giving a rev all is OK again. 

BPV in Slough could not see the problem on the TEC analysis machine so they changed the crankshaft sensor but this did not make any difference.  Spark plugs are new and generally, the engine runs very well.

Obviously (hopefully) not a big problem but does anybody out there have any idea which of the sensors could be faulty.

I thought it may be one of the following:

- faulty throttle "rheostat" which may have a bad connection for the start of its travel
- fuel evaporating from the injector feeds - possible petrol return valve weak
- a faulty sensor somewhere in the system

Any suggestions or ideas to fix this would be vry welcome.

[Max Headroom]

I can't help but 'bump'

anyone?

[nine-fiver]

I'd be suspecting dirty fuel at this point. Put in a fuel cleaner and shell out for a tank of the highest octane stuff you can. Do you normally run the tank very low a lot? if so the fuel pump may be overheating and on its last legs. But you don't know that yet...