..runs rough or stops. l have to leave it for a few moments then it starts again. my megan is a 14i and is 3 yrs old. Are there any decent mechanics out there that can diagnose the problem?

take it back to your garage and tell them it is running worse than before. they should fix it, or if it is a new problem, you will have to pay

It actualy sounds like a fuel blockage to me. Or a Damage / Blocked Fuel Filter.

I'd clean the throttle body and the idle air control valve.This will cure most stalling problems,if not then you may need a new control valve. l would also check any wiring that may cause the same fault. Here is a link to a forum that might help:

http://renaultforums.co.uk/archive/f-14-p-5.html

l had the same problem with a Ford XR3i(was 4 years old).ran ok for a while then ran rough & stopped.
l checked everything..electrics & fuel..took the injectors out..checked fuel filters & had the coil & computer checked.

It turned out that the fuel tank had some sludge in it.

The pump ran ok & only lifted enough fuel to run when stopped,then when l moved off the sludge was lifted to the pump & covered the gauze on the end of the pump intake.
By the time l had been stopped long enough to inspect the pump etc.the sludge had dropped to the bottom of the tank & everything looked ok,so the car started up again.
An odd problem only solved when l was advised to take the tank off & inspect it,having tried all other solutions.

Indicative of this problem is.drive slowly & then suddenly accelerate.
Another problem I've had with a renault(espace) which was similar..was the coil breaking down.runs ok then cuts out.leave for a few minutes to cool down.and starts again & runs for maybe a few hours before doing it again.

its a renault

It is a partial fuel blockage - possibly in the tank itself. All elements of the fuel system filtration will need to be checked/renewed. Leave tank removal until last as it is the biggest job. You say car is 3 yrs old - Is it still within warranty period?

Try the crank sensor as they are a problem with these models.
It is fitted to the top of the gearbox with a couple of screws and covered by pipes.
Cheap and easy to change if you fancy a bit of diy.
Good luck.

its very simple, u need to drag the engine out of her and filter you brake plugs then do a triple shammy on the driveshaft and replace the spark plugs, then take out the fuel injector then replace the disele with petrol, thenfailing that scrap it!!! only joking, l have no idea

faulty fuel pump could be causing this or a blockage some where.