I drive a 2002 Clio 1.4. Some months ago I experianced the same problem that the rev counter and fuel gauge does not work. Additional to this the vehicle would jerk when pulling away and the idling started to become very rough. After a couple visits to the dealer they replaced the
on the spark plugs. According to them the
and the spark plugs form a intergral part of the electronics and when the resistance is incorrect, it messes up the electronics.
I later started experianceing that the vehicle would immobilise itself when driving and then when you try and start again it would be dead. Also after many attempts I had the
computer replaced, one behind glove box. Unfortunatelly after this the original problem of the rev counter, temp gauge and jerking resurfaced.
The vehicle is currently at the dealer and they have to replace the "trottle box", whatever this does, to sort out the idling problem. They have also replaced the spark plugs. Will have to wait to see if this is going to be successful. Costing me an arm and a leg on repairs at the moment.
Suggest you start with the spark plugs, cheapeast to replace, and then look at the
on the spark plugs. They dont recommend you replace them individually but in pairs or all four at once.
Dennis (South Africa)