I just picked up a 05 XJ8 L with only 103k for only $200. It’s really clean except for a couple small cosmetic flaws. A young lady just needed to get it gone and I was the only person interested. Anyway the transmission is having issues. When it is cold it slips out of gear and is very hard to get go down the road. After driving it a few mile sometimes it goes into limp mode. If I turn it off for about 10 minutes and re start it it runs great and shifts just fine. It seems to be an electric issues. Like something is getting warm and is making a connection. I see a lot of info on similar issues but but nothing quite like what I have going on. Any thoughts would be much appreciated.

 

I would start with a fluid change, filter, and the plug that connectors the electric to the mechatronic. Find a scanner that reads the transmission codes and scan the char. Search here for the latest, a generic Code reader will only read engine codes. I have a iCarsoft i930. It was a great Jaguar tool six years ago. There are better options today.
Low fluid can trigger some of the issues you are having. If you go through the refill after flush the fluid should be back at correct level. You could just go cheap and go through the process of topping off. But it is half the effort of full service.
Your 200.00 XJ will be a 2000.00 XJ before you know it.But it will end up being a very nice ride.

 

That is where I thought I would heading next. I will keep you posted.

 

If this were my newly acquired X-350, (for $200) I would check the transmission pan for leaks and check the fluid level (no easy task on these cars). Then drive it and see if that resolves the issue. If so it is leaking from the pan or the TCM connector sleeve so I would replace the fluid, pan and sleeve and drive it for a while and see what else comes up. If the transmission is full and not leaky I would leave it alone. (why service the transmission if you've got other serious problems) Next I would replace the ignition coils with a set of name brand parts (Delphi or Denso for example) Believe it or not, subtle misfires (that do not set codes) on these cars will make the transmission pop out of gear and go into limp mode. The fact that you say that it drives normally some of the time makes me suspect coils.

I agree that you will need some level of code reader. The car probably has other deferred maintenance issues.

My goal would be to spend as little money as possible to see what quality of car it is. If it has major problems better to find out as cheaply as possible.

Good Luck
Jeff

 

A complete scan of ALL modules would get you more answers but OBDII generic reader will not do this.
Also a 'clear adaptations' would help.

 

watch this video

if its kicking you out of gear (reverse especially) it needs a new separator seal

 

IMO, "clearing adaptations" might be appropriate if you change the fluid. It will have no affect on a transmission that is flaring into neutral or otherwise having major shifting problems. Jaguar ZF gearbox programming constantly adjusts the adaptations in both directions as you drive, they don't need to be reset unless you have changed something inside the transmission.

 

I got it up on my lift and checked the transmission fluid. I didn’t have it running and well, I made a mess I must have lost two quarts of fluid. I added two more quarts fluid with it running. Then I checked the spark plugs and found that 8 and 7 where very lose. So I checked all of them and tighten the rest to spec. It had no effect on the transmission, it still was slipping out of gear. I let it rest for about 30 minutes and then took it for a drive. It still slipped for about 5 miles and then like always it goes away and drives great. I put about 40 miles on it and now I’m going to let it sit over night and give it a cold start and see where I’m at.

 

Well a possibility would be "partially" worn seals in the valve body to transmission connections.

When cold they may be not quite be sealing however when whot expansion might seal them a bit better? Just wondering out loud.

If considering changing those seals I would only do it provided there are no significant metal chaffe on the pan magnate which would mean the whole
transmission would be compromised which would be worst case scenario.

 

I'm inclined to think it is an electronic issue as it goes from problematic to working perfectly with a restart once warmed. Could be many things, e.g., a relay, a connector, ground, etc...

I may have missed it, but have you tried reading the engine codes? It would be good to know if a misfire was recorded.

I would start by repairing all of the grounds. My 2004 has three posts/studs in the area around the spare tire and three ground points behind the headlight housings. On my car, the grounds behind the headlights are bolts that run through a threaded rivet, or rivnut, rather than the studs that many others have. One of my rivnuts was spinning freely giving me some problems with the lights. I drilled it out and replaced it with a proper nut and bolt, and treated the exposed metal with some Ox-gard. I will eventually do this with all of the grounds when I have some time and I decide how I want to handle the studs in the back.

I would start by eliminating the grounds as a potential issue, as it is a good idea anyway. Then I would pull off the A- and C-pillar panels and look for signs of water damage. Also, look under the windshield wiper shroud, below the cabin filter and confirm that the connector for the ECU is clean and not corroded. If you find damage in these areas it is a good idea to clear out your sunroof drains and the cabin filter drain before carrying on. If all seems good, then I would move on to troubleshooting the coils, as JCalhoun suggested. I too strongly suspect coils or something related. To me it seems that engine-compartment heat is causing expansion somewhere which is correcting whatever fault-inducing problem you are having. I had a coil pack in a P38 Range Rover that would cause misfires when cold and then work perfectly when warm.

Best of luck!

 

I'm back from LA and I looking into the ground and the ECU tonight. THere is a lot of leaves ad junk in both the drains from the windshield. I'm betting I find something at the ECU. I just hope it's too late

 

If that is the case with your windshield drains, you likely have clogged sunroof drains too. I suggest clearing those are a priority too.

 

Following

 

Hello, maybe this will help. Last year I bought my beautiful 2004 XJ8 and immediately began getting Transmission Fault errors and car went into limp mode. I did all the research on the ZF Gearbox, took it to multiple transmission shops for a advice/rebuild cost. One of the techs told me to make absolutely sure that everything in the Engine is working perfectly. I had one code P0101 (if I remember correctly). ECU feeds the TCM so if not running correctly it will affect the TCM. Long story short, I changed out the MAF and fixed some tiny vacuum leaks. 18k miles later no more gearbox faults, it shifts as smooth as silk. I was 99% sure I needed a tranny rebuild.

Obviously each situation is unique, but something to think about.

Definitely clean out the windshield drain and the other is in the cabin filter box. Mine were clogged and water backed up in to the passenger side footwell and can short out the ECU on the other side. Good Luck!

 

Very good chance the cabin filter is the original.
Both of mine had the Jaguar name on them, & were FILTHY.
One was in backwards, indicating someone MAY have used compressed air on it
Aftermarket likely in most cars that have been changed

 

This is what I love about forums, people want to help people. I really appreciate all the feedback on my issue, so keep it coming, please!

Here is my update so far:
1. Cleaned all the drains and removed all the leaves junk to keep water flowing as it should off the windsheild, the sunroof drains were fine.
2. I was able to check the ECU connection behind the cabin filter (FYI you need a 5 star t30 tamper-proof Torx bit to remove the bolt). It was all clean and in good shape.
3. I have the transmission pan off and waiting for a replacement with all the new seals that are under the valve body. The old pan was pretty clean just a little light slug on the magnets seem much cleaning than I thought it would be.
So that is where I'm at until the new pan gets here on Monday. In the meantime, I will start to look for vacuum leaks and clean the MAF

Thanks again everyone for your help and I will keep you posted.

 

I would love to see pictures of the car. Amazing deal!

 

Here are some photos. These are after it was cleaned.

 

Absolutely beautiful car. Congratulations. I got my 2005 Super V8 with 137k Miles for $2800. It was throwing a couple codes which was cleared up with MAF sensor cleaning

 

I think it was the coils. 8 was miss firing and I moved it #2 and then 2 was misfiring. I only replaced the one but the miss fire has gone away and now I need to wait until it gets cold and try again and if that fixes the problem with the slipping. I will get seven more with new plugs. I did do a trans service and that didn't fix the problem.
I did tell my British Mechanic friend about your post and saying a bad coil could cause the transmission problem and they were very skeptical about that. I hope you are right and get to tell them I told you so. He is a friend so I can get away with it. I have my finger crossed.