Help? - Not idling from cold...

[urban]

53 Megane, 1.6 Dynamique, 41,000 miles.

When I first start the engine from cold it starts fine (and idles fine), and if I drive it very slowly with the minimum throttle until warm there are no problems. But if I have to get the revs up when still cold, it will just die at junctions etc (basically won't idle without my foot on the accelerator), then it won't start properly again unless my foot is on the accelerator - and it is like this till fully warm.

Any advice is appreicated before taking it to the garage, as I previously thought it might be the 'clutch pedal' or 'clutch switch' but I don't think this is the case anymore as symptoms become more frequent and longer - one other forum has pointed towards the 'idling valve'?

NOTE for moderator: if you spot this thread, and you can move it, i think it would be better suited in Ownership Problems!...

[AlexB]

Those who are about to shout about the history and other details of the car missing please read this thread:
https://www.parkers.co.uk/advice/forum/t ... ichpage=66

Urban,

It seems to me that the blind guessing (this is what we were doing so far) doesn't work. You know, these cars are equipped with a very sophisticated diagnostic system. The simplest thing you can do is to read stored fault codes as AntMat suggested. Much more information can be retrieved if one plugs in a laptop into the diagnostic socket and drives around logging all parameters. Then these parameters are plotted against time and the diagrams are analysed by hand. This is a very powerful method, which is not used by the dealers due to lack of education and initiative. Any independent engineer, by which I mean a skilled person with a university degree, can do it. Such interfaces are sold on ebay or, alternatively, it is easy to assemble one from parts for a tenner (ELM327 compatible). My point here is to listen what AntMat says and use the system which is already in place.

BTW, does your engine rattle occasionally? Does it use oil? Of what colour are the spark plugs?

Standard problems with these engines are dirty throttle body, ignition coils, dephasers/solenoids, camshaft sensor, TDC sensor, MAF and temperature sensors. A big problem in the UK is oil not changed annually in low mileage cars. Good luck!

[urban]

Thanks for your reply.

(Nice - unaware of inter-forum-connectivity.)

Never reaslied you could buy hardware, cables and software to access the cars interface - very interesting, will definately follow that up.

Will certainly follow AntMat's lead and find a local Bosch Dealer, as previously I've never before been recommended a garage dealership outside of warranty to use - and Renault have proved nothing but disappointing.

Unfortunately, the onboard display isn't reporting any faults and thinks the car is hunky-dory, and one previous laptop scan yielded no errors - so will definately try sourcing my own cables.

Cheers.