Hello all, I've been having some ongoing issues with my 2002 XJR w/ 135k miles and they've come to the point where I have to address them and was looking for some help, please. I realize this is a long post, but figure I should give all the issues and what I have done to the car in case there are some interconnected problems I'm not aware of.

Current Issues:

1) Throws Engine Failsafe error pretty much everytime the car is driven. Either immediately after starting, or within a minute or so. Does not go off until car is shut off, but doesn't affect drivability.

2) Throws Restricted Performance all the time also, sometimes cycles between both codes (Engine Failsafe and RP).

3) Throws High Gearbox Temperature error intermittently. Even at first cold start of the day, so I believe it is a sensor issue, not an actual overheat. Previously I could turn off/start the car about 5 times in a row and clear the error, but not today. Car won't shift out of 1st gear which is the main reason for this post today.

4) Will occasionally throw an actual check engine icon and have rough running on initial start. Feels like it is only running on half the cylinders. Very rough and waaay down on power. Usually clears up in a few hundred yards or a mile. Does not happen when driving.

5) Newest thing the Jag is doing is stalling when making a hard/sudden left turn. Started about a month ago when making a hard left from a stop across a divided 4-lane in town. Has since done it about a dozen times. It seems to be a full electrical shutdown and restart of the electrical system, not just an engine stall. The trip/mpg/speed data is reset to zero, and it takes traction control a couple seconds to come back online after the shutdown. I have checked the battery cables and battery and find nothing loose or out of place. Every time but once the car has come back to life on it's own, and I have kept going on my way after about 2 seconds of shutdown. Only once did I have to use the key to restart the car.

I've had the car for going on 6 years. Had ~90K when I bought it. Things I have done to the car (in order since ownership began):

1) Replace harness connector at trans (leaky o-ring) and change trans fluid with the correct fluid. Done at maybe 95K miles.

2) Thermostat failed open. ~100K miles.

3) Small coolant line to reservoir broke, ~100K miles.

4) Both fuel pumps, ~125K miles.

5) Trans mount, both engine mounts, air filter, spark plugs, trans filter and fluid, ~130K miles.

6) Various wear items; couple sets of tires, front brake pads, Shell Rotella T6 oil and filters regularly, etc.

OK, so what brings me here today is that when I went to start the car this AM I got a high gearbox temp error at first start, which I cannot seem to clear no matter how many times I turn off/restart the car, and cycle through P-R-D-P. The other issues I could live with, but this right now I can't get to work so I need to address this issue now.

I believe the main cause of the High Gearbox Temp error is the temp sender/harness is bad. Maybe from the oil leak at the harness from the bad o-ring I replaced prior? My plan is to see if my local dealer has the part for a not-insane price and fix that today.

I'm wondering if the other errors I'm seeing aren't related somehow, and are something I need to fix while I'm in there. Don't want to do work twice if I can avoid it. Any advice on the other errors would be welcome also! I think my linear switch may need to be replaced also from my other research; anyone care to comment?

Any input on the left turn stall issue would be great also, before it gets to the point where I can't drive the car from that issue also. Does not do it when puling away, even going WOT from a dead stop. A left turn must be involved. Never does it on right turns, not matter hard hard or sharp.

Thanks for any help,

Mike

 

Oh, I should add that my cruise control quit working when the engine failsafe/RP code started being displayed on a daily basis. Sometimes the LED in the cruise button will be lit like the system wants to be active, but even then cruise will not engage. Other times the LED will not even light up.

Rarely, I will not have an RP or Engine Failsafe code displayed, but cruise will still not engage. Even more rarely (maybe for a mile or 2 after first startup with no codes) I can use cruise for a few minutes. I used cruise daily since I bought the car and never had an issue once before, so I can am pretty certain the cruise issue is related to the error code (RP/Engine Failsafe) appearance.

Just figured I'd throw that extra tidbit out there.

Mike

 

First thing I'd do is a hard reset. When I have time later today I'll look at the wiring diagrams. You might want to follow the electrical link in my signature, I suspect you have power problems. How old is the battery?

 

Thanks for he reply AVT; the battery is at least 5.5 yrs old as I haven't replaced it since I've owned the car, other than that, I don't know.

Mike

 

Hmmm, Jag dealer is telling me I can't replace just the trans temp sensor in the XJR (you can in the non-R he says), and that I need an entire replacement valve body for $3,100……

I find that hard to believe, can anyone help point me in the right direction? Not finding what I need on Google just yet.

EDIT: Looks like he may be right, damn. Going to crawl to Autozone in low gear and see if they can clear the codes I guess.

Thanks,

Mike

 

I agree with Rob in suspecting a power problem. A new battery would be an excellent 1st step. I would then check all your ground connections and the bulk head power connection. I would also put the car up on a lift and look for any wiring that moves when the steering is turned lock to lock or any wiring that is caught between the subframe and the body

 

Rockland, ironically I actually have a lift but my 300ZX Twinturbo is DOA on it and unable to be started or driven anytime soon, lol.

Battery code shows about 6 years old.

Just went and got codes:

P0300
P0302
P0306
P0356
P1230
P1638
P0705
P1111

Looks like a bad coilpack or connector (or 2) may be the cause of the misfire/rough running.

There were a couple codes they couldn't tell me about, so I'm going to Google them.

Oh, while driving the Jag just now the check engine icon stays illuminated, and just "Gearbox Fault" is displayed. Not Gearbox High Temperature Fault anymore……..

Won't shift out of low gear obviously.

Edit: I checked the false bulkhead connector and it has a little corrosion on the forward connection. I'll clean it up. What was more interesting was that the cover for the bay holding the relays, ECU, etc was just sitting there. Someone had removed the screws previously and not reinstalled them. The ECU seemed to be held down only by compressed foam blocks on top of it. Is this normal? No mechanical fasteners like screws/bolts?

Mike

 

I could use some help on how to clear the codes. Parts stores won't because of liability and I don't have a reader to do it.

Or, is there some way to bypass the trans fault sensor?

Please help?

Thanks,

Mike

 

Do a hard reset by removing the positive lead from the battery, then touching it to the negative lead for 10 or 20 seconds. Hook it back up and see what happens.

 

Did you check all the cables in the trunk as per my troubleshooting presentation? Since it obviously starts ok, you don't have the normal grounding strap problem I'd say. I'll look over the books and see what I can find.

 

Swap the relays shown with good ones from somewhere else on the car, and really have a good look at the cables that connects the two fuse boxes on the left hand fender.
EDIT; sorry the arrows I put on there are missing! The relays are the "EMS control relay" and the "ignition positive relay".
[IMG][/IMG]

 

avt, I checked the battery cables again and the 4 cables at the box just inboard of the front of the battery, but did not do any voltage tests. Battery code date shows less than 6 years old; was replaced just before I bought the car.

I jacked up the Jag and got under it and had a good look around. Engine ground strap looked good, but I gave it some good tugs just in case. No leaks from the trans or at the wiring connector.

I pulled the J-gate shifter surround and the portion that has the P-R-N-D-etc. Nothing obviously broken or loose. I did notice the trans seems to shift into reverse a ways before the shifter gets to the dentent marked R. Not so for neutral or drive as far as I could tell.

I did find this link to the resistance values of the temp sensor at different temps:

Jaguar Workshop Manuals > XJR (X308) V8-4.0L SC (AJ26) (1998) > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Temperature Sensor/Switch, A/T > Component Information > Specificati

Looks like a 1k Ohm resistor would fool the computer unless it's looking for something more than just resistance.

I can't take another day of work tomorrow, so more troubleshooting will have to wait until tomorrow evening, or more likely Saturday.

Edit: Searching online I found info saying removing the battery cables to reset the ECU won't clear the codes. Do you know if this is correct, or what procedure or tool is required to clear the codes?

Thanks for the help,

Mike

 

The reset won't clear the codes, but if often helps weird problems regardless. Any cheap OBDII reader will clear codes. Does the shut off in turns occur if the car is sitting still? In other words, does just turning the steering wheel do it?
Another easy check is to wiggle the ignition switch and see if it has any effect.

 

I have only noticed the stalling while moving. I haven't tried to make it happen sitting still though.

My biggest concern is the "gearbox fault" and not being able to shift out of low gear. I could at least still drive the car with the other issues.

What are the odds of getting a scanner and clearing the codes letting the transmission go back to acting normal again?

 

From the transmission manual- I'd say a 1k resistor is fine.

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[IMG][/IMG]

 

A normal OBD scanner won't reset transmission codes, only engine ones. A hard reset may help, who knows?

 

"Battery code date shows less than 6 years old; was replaced just before I bought the car."

6 years is old for a battery. if was just put in it was used or sat a long time(not good). Just a thought.

 

Misfires can be due to low battery current & volts.

I'd change battery, clear codes and see which if any comes back first.

 

Lets not get too hysterical over the battery age. I suspect Beady would rather not put too much money into this until he knows it is salvageable. Yeah, I know these cars are finicky about voltage, and some of the weak battery symptoms are present, but I challenge anyone for a creditable set of issues like beady has all being the result of a weak battery. ABS, absolutely, intermittent fail safe, maybe; but not transmission stuck in first gear!

That said, the list is long and some electrical connection problem may very well be involved. I agree with the advice already given to check the fals bulkhead connector, the engine and battery straps, the voltages at the battery and then under the hood, for three conditions. 1) Engine not running, load off 2) engine not running, with lights and a/c fan running at high 3) engine running
While the engine is not running, be sure the voltage is above about 13 volts. Check again that is above 13.5 while running and the lights do not flicker much.

As to the codes. If you want to fix this car and keep it running without getting a donor car for parts, you really need a code scanner. And, my opinion is you need to get at least AutoEnginuity with Jaguar extensions. The dealer level scanner is better. Expensive, yes, except when compared to buying unneeded parts and eventually paying someone else to fix the car. You can't do much work on your Jaguar with a crescent wrench and a screwdriver, and you can't work on control systems without a way to see what is going on inside.