308 diesel stalls when warm

[theenglishrover2]

I have a 2008 Peugeot 308 1.6 diesel with around 120k on.. It's a decent car for what I need but it has had an ongoing issue. When warm, and more often when the aircon is switched on, it randomly stalls and may or may not restart immediately. If it doesn't restart it sounds like a giant sewing machine when it turns over (last time I had a car sound like that the cambelt had gone!) and when it does it's really "lumpy" for some time.

It tends to be as you slow the car for a junction or as you pull away once stopped. It can happen when the vehicle is sat idling with no input from the driver where it coughs and splutters before finally stopping and sometimes won't take input from the throttle for a while even once restarted. It has had a new fuel pressure sensor and a new EGR valve but if anything seems to be getting worse (garage said fault codes led to the EGR). I'm now wondering if it could be either the crank position sensor (as some days it drives just fine) or possibly the fuel pump. No fault codes coming up on my own OBD but it wasn't bought for this car so may simply not talk to it, and no engine management light.

Any help or input would be very much appreciated-it's now out of warranty so it's booked into my preferred garage this time and not the one the warranty company insisted on!

Thanks for reading

[white exec]

Coincidentally, I have just had this rough running at idle, and unacceptably low idle speed when warmed up and with AC or a load switched on. Fault looks to have been an out-of-adjustment anti-stall setting on the Bosch fuel pump. Car is a 1.9 BX, with XUD non-turbo engine, so not directly comparable - but does sound like idle speed dropping low, at which point the engine will not sound at all good.