Hello! I have jaguar xj8 vandenplas 1999 4.0 v8 engine.I have a problem half of engine is not working. I have tryed to change o2 sensor, but nothing changes. I have tryed to change coils, and nothing again. 4 cylinders are not working.The computer shows these mistakes (P0300- random misfire detected, P0301-cylinder 1 misfire detected, P1316-injector drive missfire emisions damage/misfire rate excess emissions) The computer shows these mistakes. one more interesting thing : those o2 sensors that jaguar have 4 of them .(2 of them are on top and 2 on bottom). I have tryed to change wires of those 2 sensors (left and righ on top ) . when i take left sensor's wire and join it with right and right sensor with left, work of engine changes. Left side of engine(which was'nt working) starts to work well and left engine side (whiche was working before ) stops to work. So i dont know what to do, maybe my exhost system have some problems or what ?

 

Hi Larys192,
Welcome to the forum. When you get chance, look in on the "New member area" it will help you navigating the forum.

If you have changed the wiring around and the problem moves with it, then your problem lies either with the sensors or the wiring to them. As you are talking about the whole bank, then start by checking the wiring and connectors on the affected side first.

Hope this helps,

 

hmm. Is it possible that exhoust system have problems? Maybe catalytic is damaged ?

 

Today I spent all day in garage. I tried to take left O2 sensor to right side and right sensor to left side and still nothing changes. just one side of enginge works. I thought maybe coils or spark plugs are wrong. so i took all coils and spark plugs from left side(not working side) to right side (working side). I changed them all and tried to start engine. still NOTHING changes. I dont know what to do more. anyone have any ideas ???

 

By changing O2 connectors from side to side you have eliminated problems with sensors, exhaust, plugs, coils and injectors. All that is left is the wiring to the O2 sensors. This wiring meets at a block in the middle of the firewall, try unplugging and reconnecting. Has that area been wet lately, or has the motor been washed?