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Discussion Starter · #1 ·
I did a search and found nothing...but patience is running very low with the day I have had.
Pulled up at an intersection and suddenly felt the car was running rough at idle...pulled into the driveway 10 secs later and switched off . Started the engine 10 mins later and the engine light comes on...indicating''deteriation in exhaust emmision values'' according to the handbook...would this be the lambda sensor or something else..any immidiate help would be great....thanks in advance...steve
 

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you need to read the codes to know for sure. A rough idle is usually caused by a cam position sensor. I had an issue where a mass air flow sensor failed, and the car developed a misfire going into "limp home mode", a restart got it going again, but set the engine management light.
 

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Discussion Starter · #3 ·
you need to read the codes to know for sure. A rough idle is usually caused by a cam position sensor. I had an issue where a mass air flow sensor failed, and the car developed a misfire going into "limp home mode", a restart got it going again, but set the engine management light.
Cheers Mike,....how do you 'read the codes' do u need to plug her in !
 

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Discussion Starter · #4 ·
you need to read the codes to know for sure. A rough idle is usually caused by a cam position sensor. I had an issue where a mass air flow sensor failed, and the car developed a misfire going into "limp home mode", a restart got it going again, but set the engine management light.
Hi Mike just had the AA out and after plugging in the laptop it read crank shaft actuator fault..is that the same as the cam position sensor ?..sorry to be a pain...steve
 

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there is also a crank sensor (not the same as the cam sensors (four of them)), not a common fault that we see here though. Could certainly cause a misfire and rough idle. It's worth having your own code reader for these cars to track down these issues. Many of us have the tool made by Peak Research, which is inexpensive and works nicely.
 
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