Persistent engine check light & electronic fault lights with limp home too
Hi folks,
I'm a newbie, and I'm hoping the group's collective knowledge can identify and ultimately help fix a persistent problem on my 172 Cup. So, sorry for the long post but here goes ...
For some time the amber check engine light has been on. It used to go away sometimes, usually on a long journey, but would come back after a few days. However it is permanently on now.
Now the amber "Preheating/electronic fault" light is also coming on (the one below the low fuel warning light). Generally it comes on a short time after starting the car and driving off. Usually the engine goes very stuttery with very poor throttle response, then the light comes on and the car is in limp-home mode. I can clear it (though not the check engine light) by cycling the ignition, but it's usually only a temporary fix, and I have to keep doing it until the car is fully warmed up. It's worse if the car is driven on a constant throttle such as cruising on a long road that has a 30 or 40 mph limit. It's worse if the car has been parked overnight in the rain. It can also come on when on the motorway or similar when I have been driving for some time at around 80mph (3750rpm) but then have to drop my speed to say 50mph in roadworks.
Even when I can get the car to run vaguely OK, it feels very coarse and down on power, as if it is running lean or retarding the timing. MPG is good though
Reading around the forum, my guess is that the upstream oxygen (lambda) sensor is gone - can anyone confirm this or suggest what else it might be?
I have had my usual (independent) garage take a look but they say they can't find anything in the fault codes. I don't know if they have a "full" diagnostic tool that can also read emissions codes
It all sounds very similar to Saturday's post http://www.cliosport.net/forum/showthread.php?t=422800
Any help appreciated as the car is becoming a right PITA ...
DanD
Hi folks,
I'm a newbie, and I'm hoping the group's collective knowledge can identify and ultimately help fix a persistent problem on my 172 Cup. So, sorry for the long post but here goes ...
For some time the amber check engine light has been on. It used to go away sometimes, usually on a long journey, but would come back after a few days. However it is permanently on now.
Now the amber "Preheating/electronic fault" light is also coming on (the one below the low fuel warning light). Generally it comes on a short time after starting the car and driving off. Usually the engine goes very stuttery with very poor throttle response, then the light comes on and the car is in limp-home mode. I can clear it (though not the check engine light) by cycling the ignition, but it's usually only a temporary fix, and I have to keep doing it until the car is fully warmed up. It's worse if the car is driven on a constant throttle such as cruising on a long road that has a 30 or 40 mph limit. It's worse if the car has been parked overnight in the rain. It can also come on when on the motorway or similar when I have been driving for some time at around 80mph (3750rpm) but then have to drop my speed to say 50mph in roadworks.
Even when I can get the car to run vaguely OK, it feels very coarse and down on power, as if it is running lean or retarding the timing. MPG is good though
Reading around the forum, my guess is that the upstream oxygen (lambda) sensor is gone - can anyone confirm this or suggest what else it might be?
I have had my usual (independent) garage take a look but they say they can't find anything in the fault codes. I don't know if they have a "full" diagnostic tool that can also read emissions codes
It all sounds very similar to Saturday's post http://www.cliosport.net/forum/showthread.php?t=422800
Any help appreciated as the car is becoming a right PITA ...
DanD
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