Poor cold start - faulty coolant temp sensor?

Hi,

Got a 2001 Clio 1.4 Dynamique+ thats started playing up when starting from very cold. It runs rough for a minute or so, sounds like it's going to cut out, produces a cloud of exhaust gases - but then fairly quickly idles normally. Once there's any warmth in the engine it runs and drives fine.

I've read online that it could well be a faulty coolant temp sensor that's not registering the cold engine with the ECU. Apparently this is easy and cheap to replace - unlike Renault who wanted £100 just to LOOK at the problem.....

Does anyone know where I can get the knowledge to replace this part and how much it's likely to cost. I'm not a full on mechanic, but I'll happy follow instructions....

Please help if you can....

Thanks.

easy to change,its on the side of the engine block will have to connectors to it and quite cheap too.
although i suspect you may have noticed some other sort of problem by now if it was this sensor.
renault may just need to re programme the ecu.also on these cars wait for the lights to go off when turning to key before operating the starter some people are just to quick for it.
what colours the smoke coming out?