UK Car Repair: Renault clio, intermittent fault, renaults

Question
My clio 1.2 16valve 2001 reg has two problems, one is that 2/3 times a week the light in the dash (shows a coil) comes on and when that happens the car an irregular Idle but after about 1mile it goes off and its running smooth until next time and the 2nd problem is the speedometer stops sometimes for a short period and then comes back on also about 4/5 times a week .
is it related and what can it be.

Answer
Hello Tom, The most common problem I have come across with the Renaults is the coil packs becoming faulty (in an intermittent fault such as yours, you should replace all four; however if you cannot afford to replace all four just replace number one and keep it. Drive the car and if it happens again replace number two with the old one from number one and so on until it no longer shows a fault). This causes the engine to run 'rough'. when you say idle do you mean idle or accelerate because if it is only the idle that is affected then the idle speed control valve would be at fault. As far as the speedo goes I would get a new speed sensor from a junk yard for a around £15 - hope this helps you - Paul