2004 Jaguar X type 3.0 engine check engine light came on Codes P0300 P0301 P0303 P0305 Any ideas what is the cause and what is the fix? Is it unusual for all these codes to come on at once? I would appreciate any help someone can give. Thanks in advance for your input.
Bluser.

 

bluser111, what you are experiencing is a common issue with the car. All of those codes are saying that you have misfires on the back cylinders (cylinders 1, 3, and 5). Odds are, you are going to need a valve cover gasket kit and then you will need to remove the intake and replace the gaskets around the openings where the coils go through the valve cover. not that bad of a job. Just take your time. It is going to more than likely take you about 4 or so hours to do this job since it is most likely your first time getting this far into the engine. No special tools. This would probably be a good time to spend a little extra money on atleast an upper intake gasket set (lower if you are questioning things) and a new set of spark plugs. This will save you from having to get back into the intake in a year or so.

Odds are, what you are going to find is oil inside the plug wells. The oil causes the spark to jump straight to the head vice making its way all the way to the plug, hence the misfires.

If you need any more details, let me know. You can get all the parts that you will need at your local auto parts store. Just tell them that you have a 2004 Lincoln LS 3.0L engine, not a jaguar. The parts are the same in this case. They will have them for the Lincoln, but not the jag (may have the upper gaskets, but that is it). You can also look on like e-bay or Amazon and see what they have too. If you look around in the posts relating to valve cover gasket replacement, you should find Felpro part numbers for everything.