Q: Very intermittent stall (once only) or rough idle after warm restart. Engine system service required warning comes and goes.

Roughly two months ago the car stalled after a warm start - it had only been off for a few minutes but was able to start after 30 minutes. It was a cold day - first -10C of the year and a full tank of gas. I had an intermittent engine system service required warning which disappeared after a couple of days. My local mechanic (not a Volvo shop) read the codes and it indicated there could be a problem with the fuel pump but the problem did not reappear. This morning my wife had a near stall (rough start) after turning it off for a few minutes after approx. 15 minutes of driving - but no stall - and engine system service warning reappeared. Once again it was very cold (-25 Celcius) and a full tank of gas.

I'd rather not replace the fuel pump if it's not necessary and so am wondering, since it is so intermittent (only twice in 2 months), if it could be something else. Any thoughts would be welcome.

Thanks

My car has 116000 miles.