Over-revving problem - help please

[telford_mike]

Posted this a while ago but got no help - maybe I didnt explain well enough..

Mate of mine has a 2001 1.6 16v Clio. First thing in the morning when cold, the engine revs to around 5000rpm all on its own (foot nowhere near accelerator). Does this repeatedly until its warmed up. Renault have repeatedly been unable to find the fault. Anyone got any ideas what could cause this?

Thanks.

 

[toms123]

Well if renault cant find it...... Most cars idle at a higher speed when its cold - my valva is about 1000rpm but drops to 750rpm when it warms up. The only thing i can suggest is gettin that haynes manual and having a good look yourself. Unlike a garage, the Haynes will be able to tell u how a certain part works and how to fiddle with it!! Sure u know all this but it really is gonna be the best solution. A renault garage wont explain like a haynes will.....

 

[Chris n nic]

I know fook all about engines but it sounds like a fault with the auto choke?

Chris

 

[toms123]

Well, the idle speed will be electronically controlled and the chances are that it will be next to impossible to adjust it. Haynes all the way baby!!

 

[crono33]

you might have a faulty throttle positioning sensor, or a air leak somewhere.

there is a valve to control idle speed, that could be faulty, or badly set, or stuck.

a quick check is to disconnect the VAE valve (the idle speed valve) and see if the engine still revs up. if it does, then the valve is oblviosly opening too much. why it is doing so though requires more investigation

im not sure it works this way in the renault engones too. usually the engine should be able to idle, when hot and with the radiator fan and all electrics off, with the VAE valve disconnected.

gm

Quote: Originally posted by toms123 on 02 February 2004
Well, the idle speed will be electronically controlled and the chances are that it will be next to impossible to adjust it. Haynes all the way baby!!

 

[telford_mike]

Thanks for these replies guys.... Bump.. any more suggestions?

 

[JAY172]

maybe a software issue.has it been reprogrammed?

if its a fly by wire throttle then maybe a fault with the moterised throttle body.

if its a cable type throttle control than maybe a idle valve fault.

 

[Dansta]

robs has a funny habit of stickin when u press the accelerator when cold, and bouncing off the limiter in neutral till u physically pull it off! lol