So I think I am having a few issues happening at once. First is I have been having a consistant issue my fuses blown it began with my Left tail light , after replacing those fuses twice it then moved to my driver side seat motor ( which took out my window and the mirror, and my seat mobility)this one I replaced three times and the third time the fuse doesn't repair my mobility, but when I turn on my ignition sometimes the seat will move all the way forward, and my last issue is a intermitted engine stall for the last few months till last week when she just lost all acceleration and the engine dies ,there I got lucky thanks to you my friends, my fuse issue it has now moved to my fuel pump fuse which just happened the second time.

oh I forgot to add when my engine stalls I get 2 faults p0727, and P1775 and my transmission triggers limp home mode.

 

Welcome aboard, John, glad to see you rescuing another X300! We're off to a slow start here but let's get to work on finding some solutions for you. Then you will really be able to enjoy driving a Jaguar!

Whenever the engine stalls while the car is moving, it is "normal" to get those two codes set: P0727 and P1775, along with Transmission Limp mode. None of that necessarily means that there is something wrong, other than your engine stalled! Notice that the Trans light resets itself after a restart, and the codes don't affect operation and can be cleared. So we must look for causes of the engine stall.

I see you have new spark plugs, and that is important. Old spark plugs will cause random stalling in this engine. The Crankshaft Position Sensor (or CKPS) can fail intermittently and cause stalling. In that case, the P0727 code would be legitimate as a CKPS failure. That part is considered a wear and tear item and it is prudent to replace it after 100k miles. It is located on the front of the engine and reads the toothed wheel on the front pulley. It might be time for a new one. However, it is hard to say for sure if that is the actual cause of the stalling. There could be other problems yet to be uncovered.

The driver's seat control module (located under the seat) is well known for acting strangely and ignoring memory instructions. It will sometimes move the seat at random, but usually only when unlocking or using the memory controls. It is one of those things that is difficult to correct as most modules out there are acting up. It's as if there were some manufacturing defects in this part.

What is the condition of your battery and it's connections? These cars can have some strange electrical happenings due to an old or weak battery. I would suggest checking the relays in the 5 fuse boxes around the car. Those relays control some very important functions, of course! Make sure they are not burned or melted, and pull them out once or twice to insure good contact.

Please let us know what you can find out, and update with more info. Let us know about recent work done, if you know of any. I'm sure much more advice will follow along here. Best of luck!

 

thank you for the info.
I didn't replace my spark plug and requested OEM plug which my local o'rielys delivered Boch super cooper plug (which didn't seem right but ok asked again and they confirm it) installed the new plugs (notice the plugs were nks bad feeling set in) while removing the #6 coil injectors one of my coil hoses broke off which I had to of course order special order and finding oil on or in #3 (valve cover gasket I am guessing ), I had already replace my <CKPS> prieviouly while initially troubleshoot this problem when tested with a multi meter the OHMs were really low. started the car and gut feeling was correct car idles was rough and could hear the misfires, back to the store for the right one and a catalytic converter bank 1 , and battery was replace recently. after putting in the right plugs it smoothed out but I am gettiing misfires and add to that exelerates without me touchting the pedel while driving and I have a flood of new codes P0121, P0400,P0300/0306/0304, P1313, P1314.......<facepalm ugh>

 

Say, John-
I am not meaning to offend, BUT language constructs, punctuation, and standard sentence structure are used for a reason. It is difficult to understand what the hell you are talking about!

 

thank you SleekJag12 for the info.

Sorry about the run on response. I tend to type and talk in my head, it can lead to missed words and punctuation errors .

So allow me to begin again,
Yes I was successful in replacing my spark plugs, but The local O'reillys gave me the wrong spark plugs when I asked for replacement OEM plug. The clerks system reported the OEM plugs were Boch super cooper plug.

While installing I had a few thing happen that gave me concern;

First was when I removed the coil injector i broke the boot . How often do these need to be replace? The one I broke and replaced was very dry and brittle, The other were in better condition. I also had to replace all the ignition coil gaskets as well as the were in just a brittle. I also noted that my plugs were NGKs not Boch and from what I read bad things happen from putting in the wrong try plugs.

The second thing was I found oil soaking the ceramic of the middle spark plug (valve cover gasket I am guessing ) the plug itself looked fine. no extra charring or pitting , none the less this is more than a little unnerving for me being a first time Jag owner.

Once I finished cleaning out the oil and finished replacing the plugs and gaskets, i started it up and She ran really rough and got a whole new set of check engine codes P0300/0306/0304, P1313, P1314.......

I went back and got the exact same plugs I pulled out and replaced them again, and she smoothed out a little but I am still getting the misfires and idles not as rough. I also have new oil dripping from the left side of the engine.
In your response you mentioned replacing my CKPS, I actually already replaced it during my first round of troubleshooting and repairs. While testing my wiring and Fuses/relays with my multimeter, my CKPS was 400 ohms below what it should have been.

You also asked about the condition of my battery which lead me to test it , we found it has a bad cell and has been replaced.

With all the changes She is misfiring and running rough but she is stalling less, but now while driving the car will accelerate without the accelerator being pressed, if I put it in neutral the engine rev. up to 60 and stays as if the accelerator is stuck. This just started happening and is intermittent.

These are the current new codes P0121, P0400,P0300/0306/0304, P1313, P1314.
Again thank you for all the help and sorry to sparkenzap for the first frantic response.

 

New 6 Pack High Performance Ignition Coil for Jaguar XJ6 XJR XJS 4 0L 5C1176 | eBay


CASE CLOSED

 

Have you actually tried those coils and know that they work for more than a couple of weeks? This forum has a long history of people buying bargain coils and finding them worthless.

 

John:
That is much easier to read! As RJ mentioned, there are a lot of reports of folks buying bad replacement coils. Check the archives for some clues as to where you might find some good ones.

I would say you should get just two replacement coils to replace the ones you see an issue with. If that does not immediately fix the missfires, then you can start swapping coils and see what codes follow which cylinders.

Unfortunately, the plug well filled with oil MIGHT be a result of the valve cover corroding through - there is a known history of this. Either replacement or trying an epoxy patch is what fixes it.

As far as the idle problem- get the missfires fixed, then we can tackle that.

 

I wish it was that easy. I would avoid aftermarket coils at all cost. They create more problems than they solve!

Thanks for clarifying John. By your codes, it seems that cylinders 4 and 6 are having trouble lighting off. You might need those two replaced. But first...

Any super copper spark plug of the right specs should work, but there is debate and differing experience on that subject. Most simply go back to the OEM Champion plugs, which are essentially proven. But as long as you have the gap set at .035" they should be fine. Another very important check is to be sure the pin which connects the coil with the top of the spark plug is clean and tight. Notice the spring inside the coil boot. It can be stretched a bit to insure good contact. File the ends of the pin to remove old tarnish or oil.

The coil boots should be intact and not cracked or oil soaked. Same goes for the coil casings. You probably need some New valve cover spark plug O-rings to stop oil from entering the wells. That's not difficult but the cam cover has to come off.

Make sure your throttle cable is not under tension, holding the throttle open. If it seems to be adjusted properly, there are other reasons the idle is high.

If you want to buy coils, please get the Made in Japan types. Those are also generally proven to last a long time compared to anything else.

Thats all for now! Keep at it.