Renault Clio III - Dynamique 1.4 Petrol 2006 35,000 miles Got a bit of a puzzle about my Clio. It's been playing up when starting from cold: erratic idling and occasionally dropping to no revs and cutting out. Despite this, it still starts first time most of the time (although it took a few goes after a three-day break at Christmas). It seems to get better once I've driven it for a while, although the engine still sounds really rough to me - almost like a diesel. There's also a high-pitched squeal when I start the engine, continuing for a few minutes into my journey - don't know if this is related but I thought I'd mention it. Anyway, I've had it into the garage and they ran the diagnostics on it. This didn't reveal any error codes but the Engine Coolant Temperature was unresponsive and fixed at what looked like -40 (I was reading it over his shoulder and haven't really got a clue). It didn't move despite heavy revving. Strangely, the dashboard temperature gauge seems to work okay. So, presuming it was a faulty ECT sensor, they had the car in again today, and replaced the sensor. However, apparently this has not fixed the problem and the reading is still the same. They're keeping it in tomorrow and are going to check the wiring. They also said there might be two sensors? (though I'd have thought they'd have checked that first). Anyone got any suggestions as to what this might be?