idle and runnning problem on a clio 16v

[Paul C]

when i start my car from cold it idles fine and when it starts to warm up and the idle drops to normal postion it starts pulsing for abou 10 seconds and the corrects itself by reving to about 1500 rpm. does anyone know what this could be as i have cleaned the idle control valve out really well sprayed WD40 over the throttle springs. it also runs lumpy and seems to bog down. when it is warmed up it runs fine. any ideas i would be greatful.

thanks

Paul

 

[Tom_16v]

Could be a number of things;

Lambda Sensor

Coolent Temp Sensor

Idle Speed Control Valve

To be honest, it sounds like the lambda

 

[RicH-]

my old 16v used to do the same thing , i was told it was the lambda , due to having a de-cat fitted...

 

[Paul C]

i have got a de cat fitted i thought that it wouldnt be the lamba as it stops doing it when it warms up?

Paul

 

[DeanRSi]

the lambda is before the de-cat though so surely it would still be reading the same as if you had a cat on?

 

[Ben j]

could be simple as is ur air filter clean? dampness gettin in ya dizzy cap?

 

[Tom_16v]

The lambda sensor is before the cat/de-cat pipe, so having a de-cat makes no difference.

 

[Paul C]

i will clean my filter tomorow but it was cleaned about 4k ago but it wont hurt to do it again. i will check my dizzy. is there any way you can test the lamba sensor? as they are not that cheap! also been advised that it could be the coolent temp sensor yes/no?

Paul

 

[Tiger]

my williams does this and has done it for ages

 

[Paul C]

p1sses you off doesnt it!! need to get it sorted then i will like it again and want to keep it!!

 

[Tom_16v]

CTS is about £20odd, genuine Renualt lambda is around £65ish

 

[JAY172]

an oxygen sensor is before the cat so removing the cat wont change the oxygen sensor readings.maybe a coolant temp sensor or a sticky idle valve when its cold.you can only read what an oxgen sensor is registering with diag fault testers/computers there are no checks that can be done on the sensor itself.

 

[Paul C]

ok mate cheers. i have cleaned the idle control valve out and i will try another throttle positioning sensor. if that fails i will try a new coolent temp sensor and then a lamba. any more ideas or do you think thay this is it?

Paul

 

[Nick Read]

Same as everyone else really...most valvers/Willys have had this problem at some time or another and it happens for a variety of reasons. Mine was down to a problem with the coolant temp sensor - telling the ECU it was cold and needed choke when it was hot, and that it was hot and needed less fuel when it was stone cold. Caused obvious problems with the idle. Dodgy speedo cables have caused similar kind of high-revving at idle problems before as well.