When car starts from cold the idling surges. When its warmed up it often stalls usually when I come to a halt. Sometimes even going around corners in 3rd or 2nd it will stall. Had a "crank sensor " fitted recently. also a new cam belt , variator and drive belt fitted recently and had clutch solenoid replaced. It had a new MAF fitted about 3000km ago. Mechanic says "the readings for the O2 sensor are out and maybe the MAF is the problem" car is 1999 has only done 80,000kms.. I'm reluctant spend more on a new MAF if its not going to fix the problem. Any good ideas?