I have a 2004 Jaguar XJ8 Vanden Plas.
I have a printout from a garage with all the errors.
Have attached.
There is alot. It was explained that the car needs a new fuel pump. This may sort out the 6 cylinders misfiring.
Just this alone is $1000. I asked about a used part and was told they have high failure rate. What about fixing it. The part looks very innocuous.
With all the other faults what do the experts think?
The sheet says battery not giving enough power which I will take back to shop to see if they agree.
It seems all the lights are lit on dashboard.

 

If the battery is "under spec" it alone can cause all sorts of faults.

Many, many instances of that issue in this forum so get it checked properly and replaced if necessary before doing anything else.

 

Not the end at all .

A bad battery can certainly cause a lot of codes . And you may well sort a lot of them with a new one ,

But your page 1 codes should not be overlooked !!

With a clean sweep of miss fire codes it sure points to fuel pump .
But
You need to do a fuel pressure test to know if the pump needs replacing .

The fuel pump motor can be purchased seperately on eBay for around $200.
And fit it to the existing plastic canister .
A massive saving , but the dealer won't offer you that .
Let's hope the cats arnt cooked already . Don't keep driving till its fixed

 

Wow, that's a lot of codes.
But, jags are known for having hissy fits when the battery voltage is low.
Modules are known not to communicate properly and throw intermittant faults.
You have HISTORIC faults showing, which says they may already have been dealt with and not cleared properly, or the drive cycle hasn't been completed properly.

There are a lot of faults on there which are not really anything to worry about much at the moment, like the instrument cluster, I suspect it's been changed, hence the mismatch fault codes and corresponding other item fault codes.
I highly suspect the rest to be connected to the dash panel and ignition barrel flap and battery.

If you have a look at this thread, it is very similar to your problem, and seems to point a finger to the J gate in his case.https://www.jaguarforums.com/forum/x...galore-101236/

 

Thanks J.
Judging by all the changes you have made to your car I presume you really really love these cars.
No doubt the model is very beautiful and certainly seems to be one of the last to actually hold dear to traditional jaguar look.
You have encouraged me to spend a bit more than I was planning on.
I figured another $700. I'll go to $2K. Sadly these year and model cars, can be bought here for $5K.
The mechanic who did the scan actually recommended "off the record" that I should be prepared to "pull the plug"

 

Thanks Datsports.
Is this the unit?
OEM 2006 JAGUAR XJ8 XJ8L VANDEN PLAS FUEL PUMP FUEL SENDING PUMP 2W939275AF

 

Thanks Steve.
Much of what you say may be true and has something to do with this j gate.
I always get the parkbrake fault showing on the console .

 

Change the battery for a new one, and then re-check the codes. Inexpensive first step.

 

I really do love this particular model Jaguar.

I do all of my own maintenance work as well as modification work as I do not have an unlimited budget. Plus I enjoy what I do and with no time constraints.

 

Go Makos!

 

What problems are you actually experiencing with the car? Just the Check Engine Light?

Going by that list of codes as a "to do list" is folly. Cars generate all kinds of random errors that may occur for a second and never return. Clear that list first, then focus on the actual issues.

I agree with the above, if the battery is suspect replace that first. If your engine is running lean you won't kill the catalytic converter, running rich will. But it may already be on its way out.

 

Well this is perplexing.
A friend checked battery at rest and under load and said it was fine. I took it to auto store where I bought it under one year ago and they, too, confirmed battery is good.
What am I to believe about the report from Jaguar mechanic with supposedly correct diagnostic tools? Numbers can hardly be subjective. Either battery is not working as it should or it is.

 

The actual issue is the engine sounds strange. When I accelerate the engine sounds as though it is cycling on and off. The engine seems to labor under acceleration seemingly every time above 40mph. The engine gets louder and has a different sound. When cold the transmission jerks into gear from standstill.