Citroen C5 Running On 3 Cylinders

[Guest Jesseron]

I have a C5 1.8 LX petrol 16v on a 52 plate. She is running on 3 cylinders. Firstly i changed the spark plugs & put new bosch ones and also replaced the petrol injectors. I then put in a new coil pack but still no change. One cylinder is not firing despite petrol being fed into the chamber. The plug for this chamber on inspection shows unburnt petrol . Disconnecting the injector electric supply to this chamber does not have any effect but doing so for any of the other 3 injectors makes the car worse off so i definitely know its this 1 chamber giving probs. There is no indication of compression loss in this chamber as turning over very quick and not hunting.Having changed the plugs, injectors & coil pack ....i am stuck. S O S PSE!!!

[Randombloke]

Crankshaft position sensor not working properly?

[coastline taxis]

when the engine is running unplug the multiplug and use a multimeter to see if its sending a signal to the injector

[paul.h]

A compression test will show if there is a valve or head gasket problem if fuel injection and ignition are found to be ok. Is the engine management light on ? Can you smell petrol out of the exhaust showing the exhaust valve is opening but also could be damaging the exhaust catalyst ? Any unusual noises from the top of the engine ?