One of my friends has a Citroen Xantia 2.0 16V Petrol (RFV) with Bosch MP5.2 control unit.
The car stumbles and hesitates badly especially under high load acceleration.
The car has a fast idle @ around 1100 RPM. (maybe vaccuum leak).
When the car is warmed up, the MAP reads 420 - 440 which is quite high and despite high manifold pressure the injection pulse width is only 2.2 - 2.4 ms!! Strange!
I hooked up Lexia and the following DTCs showed up:
I unplugged MAP sensor and went for a drive. It didn't improve the situations and the only thing that happened was the engine cutting out when I let off the throttle. Should an unplugged MAP make the engine to cut out with throttle closed?
I plugged back the MAP and unplugged TPS and that didn't see, to improve the situation either.
I listened to the clicking sound of each injector and it seemed that cylinders number 2 @ 4 had sluggish clicking sounds. I removed spark plugs and noticed that cylinders 1 @ 3 had almost normal looking plugs with whitish center electrodes but number 2 @ 4 had fouled spark plugs which i think is the results of rich condition in those cylinders.
The car spits a lot when i stand near exhaust and it doesn't idle smoothly.
My friend told me that he unplugged injectors with the engine running and some of them didn't change the engine behavior.
I suspected the fuel pump but i doubt about it because a weak fuel pump will affect the whole cylinders not just two of them.
Could it be the injectors?
Should he replace the MAP first?
They are both very expensive.
