1.1 Idle Problem

[andy1966 3]

hi guys

i have a problem with the tickover on my 205 it seems to be over fuelling and is very uneven on tickover i replaced the plugs and leads on it yesterday it ran better but still uneven on tickover i also relaced the water temp sensor still no change but what i did notice is if i leave the water temp sensor unplugged it runs perfect but the problem then is its ticks over a little high but does actually run perfect and when i plug the water temp sensor back in its running very poorly on idle has anyone ever had this problem if so any ideas how to sort it would be a great help

thanks

andy

[TooMany2cvs 65]

Is this an injected 1.1?

[andy1966 3]

hi adrian

yes its injected looking in the manual it has the MMFDG6 system on it

[TooMany2cvs 65]

I don't know that system at all, but all the usual injection checks apply. If the coolant temp sensor is indeed good (Definitely the right one, not one for the gauge/light on the dash? Checked the resistance at a range of temps, both at the sender and the ECU pins?), then I'd probably start looking at the throttle position switch adjusted up and switching properly? Air leaks? Idle's a stepper motor on these? Give that a damn good clean with carb cleaner.

[andy1966 3]

hi adrian

theres no air leaks the top end of the engine has been rebuilt and every gasket and seal has been replaced due to it having a blown head gasket when i got it the water temp sensor is new and the correct one as for the gauge light on the dash its not wired up ive fitted an elecric temp gauge with a new temp sensor into the thermostat housing.

like you said think ill look at the throttle postion switch next and give everthing a damn good clean with carb cleaner and see what happens

[welshpug 1,626]

does it have a lambda sensor?

 

a blowing HG often kills these off.

Edited October 1, 2013 by welshpug

[TooMany2cvs 65]

theres no air leaks the top end of the engine has been rebuilt and every gasket and seal has been replaced due to it having a blown head gasket

Has it behaved since then?

 

when i got it the water temp sensor is new and the correct one

But is it giving the right resistances, both at the sender and the ECU?

[andy1966 3]

well like i said with the water temp sensor unplugged it seems to tick over alot smoother but then the problem is the tick over is just a little high with the sensor unplugged and while its running if you plug the sensor back in the tick over starts to be rough agian ill check the resistances in at the week end ill have to consult the manual as ive never done that sort of test before

[andy1966 3]

does it have a lambda sensor?

 

a blowing HG often kills these off.

yes it does have a lambda sensor and the headgasket was blown when i got it ive since done the headgasket

[welshpug 1,626]

unplug that, stick the coolant temp sender back on, see what happens.

[andy1966 3]

unplug that, stick the coolant temp sender back on, see what happens.

just been and tried that and it worked the car is now running perfect and ticking over properly.

[welshpug 1,626]

bingo, you need a new lambda sensor

[andy1966 3]

bingo, you need a new lambda sensor

yep looks that way thanks for your advice helped me alot