Right, my rs1800 wont run on idle. the car starts fine and drives beautifully, but as soon as the revs drop below about 1000rpm the engine cuts out. the car will start again fine though. Im thinking a connections lose or somthing as this has ust started happening about an hour ago. any help greatly apprieciated!

 

Try taking the idle speed control valve out and cleaning it out in petrol or white spirit as these are prone to playing up

 

the idle speed control valve is only a couple weeks old, pretty sure its not that. but thanks.

 

UPDATE: the car will run on idle perfectly when its cold, as soon as its warm/hot it just cuts out below 1000rpm. it doesnt run lumpy at all just cuts out.

 

take a look at this might point you in the right direction

http://www.btinternet.com/~madmole/Reference/Idle.html

 

problem seemed to have fixed its self, but this guide is extremely usefull. thanks alot buudy.