Join Date: Feb 2011
Location: Canberra, Australia
Car Year: 2010
Car Model: Forester Diesel
Feedback Score: 0 reviews
interesting issue (for us) and no doubt frustrating issue for you!
We had our 2010 cut out once on a freeway on-ramp under full throttle. Luckily it was a downhill ramp and the engine cut back in by itself.
Only ever happened once, shortly after that we had a split turbo elbow/piece. I'd suggest you check all the intake hoses/pipes for splits, looseness or leaks. This may not be the issue but it's an easy one to do that hasn't been mentioned yet and is common on these vehicles, especially 2010 ones.
Apart from that it could be a multitude of things and I'd suggest a proper diagnosis from a proper readout, like subdiesel suggests (G'day subdiesel, good to see you're still watching :-) ) may be instructive as it will show what is happening at the stall- what may be varying, out of spec, abnormal, etc. It could be anything yet from a valve timing issue through intake, fuel control, sensor, ECU failing, malfunctioning solenoid/valve, excessive carbon buildup or even just a loose ground connection.
As karlaudi says, it's unlikely it's the fuel itself now and it's good that the basics have been checked. A good professional scanner readout with real-time (Mode6?) data of multiple parameters is what you now need for further insight. If your mechanic hasn't done that, then they're perhaps not quite THAT good...unfortunately these are not 'old school' diesels and need more than a oil bath air filter and a bleed of the injectors every so often.
2010 Forester Diesel (wife's now)