Clio 172-engine goes to high rpm alone,bad idle

[Mirec8684]

Hi guys. I need your help, because at this moment I dont know what could be wrong with my car(Renault Clio Sport 172,year 2000). I saw some threads, but without results. My problem is, that idle rpm is high (cca 1250) and rpm always goes high alone, without pressing pedal and sometimes after pressing pedal. When I drive and have neutral is problem to get to 1st. or 2nd,.....gear,because high rpm. Back gear is big problem get. I feel, when I drive that cars goes faster alone. Its not driveable.

I replacement all gasket on intake manifold and other parts, check live data (map sensor - idle about 300mbar, when goes rpm high alone about 250mbar - without pressing pedal)-(air,water temperature - ok, car without diagnostic codes), check sealing injectors, hoses, compression test,sealing map air temperature sensor. When I put my hand on the throttle body engine goes off after 1s and it suck my hand enough strong. Try replacement idle control valve, throttle body and clean all (old and new used), try another throttle position sensor (check reading with diagnostic tool-the same old and new).

Throttle cable is without damage and without hack. And I also check to clog all hoses, inlet to intake manifold to have just throttle body free, without results. I really need your help with this weird problem. Thank you for fast answer.

 

[Mbeau]

I have found more often than not the cause of high idle is an air leak. Is everything connected correctly on the inlet manifold(nothing trapped causing front or rear not to seal correctly).

Is the butterfly in the throttle body opening and closing as it should.

 

[White16valver]

@Coops Mk1 - do the 172s have the same sensor as the F7P/F7R engines, the one you mentioned before, which fails and prevents the idle from dropping between gear changes??

 

[STEVE.M]

Hi guys. I need your help, because at this moment I dont know what could be wrong with my car(Renault Clio Sport 172,year 2000). I saw some threads, but without results. My problem is, that idle rpm is high (cca 1250) and rpm always goes high alone, without pressing pedal and sometimes after pressing pedal. When I drive and have neutral is problem to get to 1st. or 2nd,.....gear,because high rpm. Back gear is big problem get. I feel, when I drive that cars goes faster alone. Its not driveable.

I replacement all gasket on intake manifold and other parts, check live data (map sensor - idle about 300mbar, when goes rpm high alone about 250mbar - without pressing pedal)-(air,water temperature - ok, car without diagnostic codes), check sealing injectors, hoses, compression test,sealing map air temperature sensor. When I put my hand on the throttle body engine goes off after 1s and it suck my hand enough strong. Try replacement idle control valve, throttle body and clean all (old and new used), try another throttle position sensor (check reading with diagnostic tool-the same old and new).

Throttle cable is without damage and without hack. And I also check to clog all hoses, inlet to intake manifold to have just throttle body free, without results. I really need your help with this weird problem. Thank you for fast answer.

A lot of points were raised in this thread.

https://www.cliosport.net/threads/p...acement-help-and-advice.788421/#post-11288626

 

[Coops Mk1]

not in the same way @White16valver, they may have some form of idel control from road speed sensor but its not on the cable like a mk1 as trhey don't have cable speedo

if its doing it before driving that's not the fault anway

I would simply say, if the throttle cable hasn't been changed, change it, even if they feel free and fine, they can still cause enough drag to affect the throttle body when they age. replace that for new genuine Renault and see how you go.

 

[Mirec8684]

It does it almost whole time after start, not just between change gears. And throttle cable was disconnect, I tried it and the problem is still there. Its really weird. PRessure at idle is 300mbar, so I think intake sealing would be good. I think its not bad value.

 

[White16valver]

not in the same way @White16valver, they may have some form of idel control from road speed sensor but its not on the cable like a mk1 as trhey don't have cable speedo

if its doing it before driving that's not the fault anway

I would simply say, if the throttle cable hasn't been changed, change it, even if they feel free and fine, they can still cause enough drag to affect the throttle body when they age. replace that for new genuine Renault and see how you go.

Thanks for the confirmation!

 

[White16valver]

Could it be something related to the Lambda sensor??

 

[deanoE30M3]

Try the throttle cable, I had mine do it and the throttle cable was dry and catching!!

Got real bad revved on it’s own!