I had a misfire 3weks ago, done some google and ended up replacing coil/plugs/leads, this fixed it and was running fine, but on wednesday i was sat at road works for around ten mins and when i drove away it started to missfire again, drove home and thought nothing of it. Next morning it started nd drove fine but the moment im sat in traffic it will develope the missfire. Any ideas.???

On the way home today the missfire started after stopping for road works, i pulled over and turnd off the car and popped the bonnent (was going to unplug the maf and check that). Before i unplugged the maf i started the car and it worked fine - no missfire.???

Extra info, 144,000mile on the clock, i replaced the water pump 2weeks ago, dosent over heat, the missfire only happens at below 2000revs.