renault megane randomly cuts out

i have a renault megane 1997 that usually runs fine, but sometimes when taking my foot of the accelerator to get ready to change gear the revs will rapidly drop and the engine just cuts out. it starts up again instantly and then will carry on running perfectly. it usually happens within the first 5 mins of starting the engine and after a short while i wont have any trouble with it at all.

hi there, it looks like u got a problem, so can u tell me more information like is it cold or warm weather? do u have a problem in the morings or in the day? by the sound of it, it looks like the crankshft sensor is dirty or maybe needs changing. look at that first because i had the problem on my renault. tell me know how u get on!!
cheers mark

hi, thanks for replying.
the problem is mainly in the mornings when it is cold. for the first few mins of driving it will always cut out when i need to go into first gear for a junction but as soon as the car warms up its fine.
but sometimes after driving around for a long time the car will begin to over rev alot in first gear and its very loud going at about 40 000 revs in first gear.

right sounds like u need a crankshaft sensor, so put a new one in which is on top the gearbox at the side of the engine. if u r still having trouble let me know ok. cheers mark

I would clean the one you have first before buying a replacement...usually works