I have a 1999 2.0 Ltr i Nissan Primer Estate.
At its last MOT it failed on very high C.O levels at idle speed (6.8 compared to 0.3 which it should be).
At 3000 revs the C.O is exactley what it should be and the car runs like a dream.
At idle the engine revs fall to almost stalling point about every 30 secs and then the C.O readings go up to 9.5. This to me shows that the engine is getting a burst of fuel for some reason.
It has been taken to a very good Nissan main dealer (who I trust) who as of yet have not been able to trace the cause.
They have checked the ECU and run diagnostics on all related sensors, several sensors have been replaced even though the diagnostic equipment showed them to be working, injectors have been tested, spark plugs have been changed and fuel pressures checked, the list goes on and on.
The technicians have contacted Nissan technical support, they could only go over what the Nissan dealer had already done and agreed that the problem should be down to a sensor like the oxygen sensor.
I now have the car back with the problem still not fixed. I am losing the will to live and have thought about trading it in, but lets face it what dealer is going to give me good money without an MOT.
I am hoping that there might be somebody out there who has seen a simular problem or can think of what might be the cause. Theres no harm in trying.
If you think you can help please respond to this.
Thanks
Brad
At its last MOT it failed on very high C.O levels at idle speed (6.8 compared to 0.3 which it should be).
At 3000 revs the C.O is exactley what it should be and the car runs like a dream.
At idle the engine revs fall to almost stalling point about every 30 secs and then the C.O readings go up to 9.5. This to me shows that the engine is getting a burst of fuel for some reason.
It has been taken to a very good Nissan main dealer (who I trust) who as of yet have not been able to trace the cause.
They have checked the ECU and run diagnostics on all related sensors, several sensors have been replaced even though the diagnostic equipment showed them to be working, injectors have been tested, spark plugs have been changed and fuel pressures checked, the list goes on and on.
The technicians have contacted Nissan technical support, they could only go over what the Nissan dealer had already done and agreed that the problem should be down to a sensor like the oxygen sensor.
I now have the car back with the problem still not fixed. I am losing the will to live and have thought about trading it in, but lets face it what dealer is going to give me good money without an MOT.
I am hoping that there might be somebody out there who has seen a simular problem or can think of what might be the cause. Theres no harm in trying.
If you think you can help please respond to this.
Thanks
Brad
