My wife has a 2007 Mazda 3 with the 1.6l petrol engine with an approx mileage of 55000.

Ever since she bought it a year ago the car has had an annoying and sometimes dangerous problem that the local Mazda agent dismisses as nonexistent. The car starts perfectly and runs smoothly when moving at speed. The problem is when the engine is warm the revs dramatically die as you slip the clutch and pull away in first gear before picking up again. This has resulted in us having to overrev the engine to ensure the engine doesn't die when pulling away from junctions etc. If we let the revs die too much then the car jerks down the road as if a learner is driving until the revs pick up.

It is less of a problem when the car is cold as the revs are raised by the auto choke. I can "override" the factory set idle speed to mimic the cold running speed, but this of course totally upsets the ECU and so isn't a way forward. I understand that the throttle and clutch are linked by microswitches and was wondering if there was a fault with either/both of these switches, or maybe something in the ECU itself.

Anyone got any ideas as Mazda say there is no problem!!!