Nissan Repair: 53reg nissan primera engine management light, fuel pressure gauge, fuel pressure regulator

Question
hi i have a Nissan primera 1.8 petrol 53reg the engine management light is on and RAC put it on their computer and told me the engine lamber exhaust sensor is not operating I have changed the two exhaust sensors few times but the still seams to miss fire and my fuel consumption has gone down. I could smell the engine sometimes as it is burning  rich, Regards bashir.

Answer
Bashir,

If the sensors have been replaced recently I would check the ful injectors to see if any are leaking.  You can pull the sparkplugs and note which hole thy came from.  If they are black with soot then you have an over rich condition.  You can get a fuel pressure gauge and see what the pressure is and compare it to the service manual readings.  You probably have a problem with an injector or two or the fuel pressure regulator going bad.  It could also be something as simple as a bad vacuum line to the regulator.  Email me back if you need more.