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unknown cause of misfire p0306 code.

 
  #1  
Old 05-06-2016, 09:20 PM
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Default unknown cause of misfire p0306 code.

Engine light is on and flashes when driving about 45mph. Ive changed coil and plug #6. I have scanned the vehicle and my fuel trim on bank one drops to zero. I have also done a fuel pressure test and come up with variants from 30 to 38. When I shut car down and just turned key pressure was at 50 but dropping real slow but didn't hit quite as low as 30. Ive had the manifold gaskets changed about 5 months ago, so my leak stopped but since I own car 3 years its always been a hard start. ive swapped out the fuel filter and have ordered a new fuel pump since this is an easy fix and 3 others along with some threads I have read point to this. Oh.. did I mention its my wifes car

any Help?
2001 s type 4.0 las vegas
 
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Old 05-06-2016, 10:29 PM
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When you replaced the coil and plug, did you notice any bad wiring to the coil? Did you use genuine Jaguar coil or aftermarket? And did you replace the correct one, for a 2001 V8, cylinder 6 will drivers side of engine, 2nd cylinder back from the front. Assuming you did that, if the wiring is ok going to the coil, it is possible the fuel injector is faulty. Are you able swap the injector to another cylinder and see if the code moves to that cylinder?
 
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Old 05-06-2016, 10:42 PM
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I replaced using ngk plug, I purchased a coil from oreillys I think motor craft. I havent tried switching the coil yet. the wires look ok. Im going to rent a compression tester to see if valve is bad. Im wracking my brain with all the info on a vacuum leak here on the forum. When you look at the science it points to oxygen. I was advised to clean up all tubes and connectors also.
 
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Old 05-06-2016, 10:52 PM
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im not sure how to swap injectors. I guess i'll do more searching


2001 s type 4.0
 
 

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