Hi there David - I also have a 1997 P reg 1.6 Rt Auto Renault Megane Scenic which by the sound of it has the same fault as yours. It clunks and lurches slightly as I pull away from standing. It was my sisters car originally - she took it to a Renault dealership in Norwich and they told her it was a lubrication problem in the automatic gearbox but because it was a sealed unit it could not be fixed it could only be replaced. When I acquired the car I asked my local Renault dealer about it and they gave me the same story so it must be a common problem I reckon. Basically it would cost more than the car is worth to replace the gearbox so they more-or-less said just "drive it until it fails". They said it could be weeks or it could be years before that happens. That was a couple of years ago and the fault is still there but now there is a starting problem as well! anyway I know this doesn't answer your question but it may shed some light on it.
David Bell
August 2007
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