Hello everyone.

First post here - a long time fan of the marque and one day, I will own one, or four....

Anyway, like most people and I apologise for this, I am joining to ask for advice. It is actually on behalf of my father, who has a 1989 300CE, a lovely car with all the toys and plenty of presence.

However, since acquiring it last April, it has an annoying problem that only manifests itself in cold weather. It will start fine and run OK for ten minutes. Then it will begin to run rough and seems low on power, before it cuts out and it is a struggle to start again unless another ten or so minutes passes, after which iy starts fine and runs perfectly.

My Dad thinks it is an automatic choke which is engaging and then failing to disengage once the car has warmed up, causing it to run rich and flood. Does this sound plausible? Does a fuel injected engine have an automatic choke? The workshop manual doesn't offer much assitance here.

Any suggestions where to look? Thd car has done 155 000 miles and is fine in summer - it is only the cold weather that bothers it.

Any help much appreciated and thanks for reading.

Cheers