2004 Jaguar XJ Vanden Plas ~90k miles

I got back into town last night and this morning jumping in my car to head to work (car has been sitting since Sunday) i immediately notice it is idling/running rough (sounds/feels like a misfire or 2). Restricted Performance message, and a service engine light are lit. As soon as I start driving the engine light starts flashing. I had no choice but to drive it today, so I did so carefully and gently. On my way home stopped and read the codes, which are as follows (with what I believe them to signify in parentheses, please feel free to correct):

P0171 (lean bank 1)
P0174 (lean bank 2)
P0300 (generic ignition misfire code)
P0306 (misfire cyl 6)
P0308 (misfire cyl 8)
P1314 (?????)
P0206 (fuel injector cyl 6)
P0208 (fuel injector cyl 8)
P1111 (non-fault ECM cycle complete code)

The previous week or so, I had noticed the check engine light come on intermittently (usually on 'colder' days here in Florida), usually for a minute or two at most, never flashing, and with no noticeable change to cars performance/operation. I checked the codes then, and saw the P0171 and P0174 (the lean conditions) so I suspected maybe a vacuum leak that got worse when cold, or a MAF or similar. I had a crazy schedule and planned to take a look at it once the holiday season was past.

Does anyone have any experience or suggestions with this particular combinations of codes? Obviously something is going on with cylinders 6 and 8, but I dont want to just start "shotgunning" this by throwing parts at it to see what fixes it if I can at all avoid it. I'm not familiar enough with the electronics and control systems on these engines to have a good idea if there's a single component failure that could could this combination of codes/faults. Any help or suggestions is appreciated. Thanks!!

 

First, check fuel injector electrical connections at Cyl 6 and 8 - ensure they are fully seated in the injector.

Was any recent work performed in this area??

Also, not wise to drive with a flashing CEL - unspent fuel going into exhaust - will easily take out your cat converters...

 

Had the dealer replace the front air springs with arnott rebuilds about 3 months ago, car has been driven daily since then.



Meant to ask this in original question... anyone know the cylinder numbering convention for this car (ie, which is 1, 2, 3, etc)?

 

I'm having the exact same problem since yesterday. No work done in that area. Please help

 

Hi RocketScientist,

See the diagram below. The arrow indicates the front of the car.



The diagram is from Page 3 of the X350 OBDII Diagnostic Manual available at this link:

http://www.jagrepair.com/DTCforms/X350_P_DTC_OBD_II.pdf


Cheers,

Don

 

Check that the plastic intake engine to filter air-box does not have any holes in it, especially underneath, or PCV hose being cracked open. Cracks and engine movement mess up the air flow and cause massive lean conditions and movements then close and cause massive over fueling or spark misfire and then fuel in exhaust and then teh sensors sense this and flash.

Just had this exact situation on another car

 

Flashing MIL = misfires so bad they're damaging the cat(s).

 

thanks for all the info so far guys. When I get home today I will check fuel injector harness/connectors and leaks in airbox as suggested. Will report back with any results. Thanks so much!

 

Well you guys will never believe what the problem was... or at least I would never have guessed it. Squirrels. F***ing squirrels chewed through the injector wires for cylinders 6 and 8 right where they come out from the main injector/engine wiring harness bundle. We have a huge oak tree in the front yard that had a bumper crop of acorns this fall/winter, and it looks like they were stashing them in the little recesses of the intake manifold, under the engine cover. Guess the wiring got in their way and they chewed through it while I was out of town.

My dad gets back in town later tonight, and he's a career aviation electronics tech, a wizard with wiring in tight spaces. Hopefully he and I will be able to splice the harness back together and that will be that. If not, does anyone know of a good source for replacement parts, specifically the front engine/injector harness? I spent about an hour combing the internet trying to find one and have had no luck... is this part even available? Or something I'd have to get from a salvage yard or (gasp) pay the dealer to replace? Thanks for any help!

 

I had a feeling it was the injector electrical connectors but ugh!

Best bet you will need to source through a salvage yard (if your lucky) or just solder in proper gauge wire to restore each electrical connector - 2 wires per..

Good Luck

 

Well, got the old girl back on the road today. Peeled back the sheathing for the engine wiring harness enough to get a few inches of slack on the cut wires, trimmed off the bad portions on each end, used PIDG crimps and a few inches of 20 ga wire to splice them all back together. She runs like a champ, and after clearing the codes, none have popped back up (yet... fingers crossed). While I was in there, I noticed some other squirrel damage. They chewed through the feed hose for the driver's side windshield washer (where it goes from the cowl to the wiper arm). In that same area of the cowl (in the pocket/recess for the wiper arm) there is a drain hole that leads to a soft plastic pipe going down under the car. They enlarged this hole, and ate through the top half of the soft plastic pipe. That whole area inside the cowl (under the access panel, where the brake booster and such is) was filled with leaves and fiur and acorns. Ugh. I cleaned things out and patched stuff up pretty satisfactorily. Looks like I'm all back together for now.

Now all thats left is to determine what to do about these damn squirrels. I'm thinking full-on warfare. I have some live game traps I can use to catch em (and drown em), and a nice blowgun for hunting the clever ones... i live in the 'burbs, so even though I have a suppressor for one of my .22s, thats probably not a good idea from a safety standpoint. Good news is fried squirrel is delicious for breakfast, so they wont be going to waste.

Thanks for all the help guys. Have a great weekend.

 

A few years ago squirrels chewed their way into our attic and I was faced with the same dilemma. Live-trapping them removes only one at a time and becomes tedious very quickly. I don't know about Florida, but in Tennessee the hunting season for red, gray and fox squirrels runs from late August to the end of February and the limit is 10 per day, so the state is essentially begging hunters to reduce the population. In our subdivision I've found that an air rifle is a safe, legal and effective solution.

 

Tales of squirrels eating one's car are very rare here in the UK, even though we have lots of your US greys running around. Maybe they are on speed or something !!

Or maybe you don't use the Jaguar a lot. I did have mice eat through a newly installed Mark 2 headliner once back in the 80s. Not a nice surprise when you are a poor man !!

 

I was as surprised as you were. I drive the car daily, though preceding finding the wiring chewed through, it had sat for maybe 3-4 days while I was out of town for a funeral. We have a big oak tree in the yard, and this year it dropped a LOT of acorns, We've all commented on how crazy the squirrel population has been going this season, maybe they were running out of palces to stash everything. Doesn't matter now. Theyre all going to die, and end up in my belly. Kinda looking forward to this.