I don't know if joycesjag has mentioned anything about this, but around this past October, I bought a 2003 XK8 convertible. It was functioning fine at first. The only problem at the time was DSC System fault, but that warning light would go on and off. I bought it with over 123,000 miles from someone in Tennessee who originally bought it from Scott Jaguar in Charlotte, NC. It had trouble turning on, but when you would hold it for a few seconds, it would go on. A few weeks later, I suddenly have a gearbox fault and the check engine loght goes on. I also notice when the DSC Sytem fault would show up, sometimes the ABS light goes on. I've also had random things happen like the transmission sliding from all this. I first go to joycesjag (and please contact him as well), we change the spark plugs, check if there's anything wrong with the fuel filter, but it looked fine. We get Bosch Iridium plugs. I then take the car for a diagnostic at Leith Jaguar and they tell me before anything, my valve cover gasket needs to be replaced, my spark plugs need to be replaced (although I told them mine were just changed, they suggested to use NGK plugs over the Bosch ones I bought), and suggest for cleaning the fuel injector, performing an air induction service, and also do an engine management update. I go back to Leith Jaguar, get the fuel injector cleaned, do the air induction service, and the engine management update, and also do another diagnostic to try to determine what is causing the gearbox fault. From what Leith Jaguar told me, they suggested me to get a new transmission or get a used one. There reason was when their machines/devices or whatever were trying to communicate with the transmission and the transmission control module, none of them "responded" back with a status. They did say it could be the transmission control module or the transmission, but suggested going with the transmission. joycesjag and me are trying to do research and really see if that is the case. joycesjag and part of me believes its not the transmission and something else. Also, recently (joycesjag doesn't know this yet) I had an engine system failure. It happened to me twice while driving. Both times, I pulled to the side, turned off the car, turned it back on then it was fine. The third time however, I couldn't turn on the car, and it got stuck at a Harris Teeter parking lot, then I tried as many times as I could to turn on the car, then a friend of mine got it towed to my house. I do have an image of the diagnostics and will try to upload them here soon, but any help would be greatly appreciated.

 

This is the image of the diagnostics and repairs done so far

and here's a link in case you can't see it well:

http://oi45.tinypic.com/24xp3x4.jpg

 

This is almost the same issues that I am having. Can some one please tell me how to inlarge the pics. My threat is the cat has a mind of its own.

 

I honestly don't know. That is why I put a link up for mine. I'm not on this forum enough to know

 

I just the car home from Greenville tonight and I am going to check to see what new codes have been set. I think that I have a moisture problem that has cause so sensor issue. Drove thru flooded roads and heavy down pours. Will be up dating my thread in the morning. I did get it to enlarge and used the old reading glass. Thanks Jim

 

to enlarge the pics open from the link provided, when that window opens, click the view pulldown at the top of the browser window and select zoom - you can now enlarge to a readable pic.

 

Steve thank you

 

A little help please with my first 2 posts? I don't really know what's best to do with my current situation

 

Your problem is so complicated it hurts my head. BUT, it sort of reminds me of the problem I had in that there was no cruise control, but no codes. IDS from a indy said the TCM was not communicating.
I suspected a connection problem in the CAN bus, copied the relevant elec. diagrams, and proceeded to check and clean all the connectors and wires in the CAN bus from the instrument pack, through the trans. switches, BPM, CCM, bulkhead connectors, etc. to the TCM and ECU. This with the battery disconnected, of course.
I still don't know where the problem was, exactly, but the cruise control works now.

 

I see. When the ABS light goes on (which it doesn't always) it would ruin my cruise control. I'm gonna attempt something Reverend Sam posted to fix the ABS/DSC System fault. Here's the post I'm basing that off:
https://www.jaguarforums.com/forum/x...ors-faq-37434/

I really need to know where to begin with the gearbox fault. Also, is it actually necessary for the valve cover gasket to be replaced?

 

Regarding the valve cover gasket, the dealer inspection said there were severe leaks, so the gasket should be changed. If the leaks are outside, you would probably smell oil, If the leaks are inside at the spark plug seals, this could be contributing to your misfire problem.

Regarding the ABS faut, certainly cleaning the sensors will not hurt. Generally if the fault comes up when you are moving, the sensors or sesnor cables are likely suspects. If the fault comes up when you first start the car it could be nothing more than a weak battery. Have your battery load tested for free at Autozpone or Advance Auto. If the fault comes up at a standstill, it could also be the ABS module, which has a known problem with a bad solder connection at the connector. Search the forum, this is not too hard to fix yourself if you can solder.

Regarding the transmission fault, I would suggest getting a second opinion from an independent Jag repair shop.

 

You need to read this first and see if it applies

Link JagRepair.com - Jaguar Repair Information Resource

If you can could you provide the codes you are getting?

 

Hi.

As always, the first thing to check is that you have a battery that is fully charged and will keep the charge.
- Check thick leads, both positive and negative, going from battery to aft main fuses, They may corrode over time and lose their conductivety.
- Check all fuses applicable to your problem areas.
- Ensure all, and absolutely all relays are properly seated. They may work loose over time. Any corrosion, a small squirt of contact spray. Don`t drown it.
- Go over all connector plugs you can find, and especially the ones mentioned below. Check for corrosion and bent pins. Some of the pins are very tiny.
- ABS/DSC
- Check connectors to ABS module and pump
- Clean all four wheelspeed sensors
- Check conductivety and resistance in harness to sensors
- You may have to resolder two pins inside module
- Transmission fault
- Check connector to TCM (Transmission Control Module)
- There is a rotary switch mounted on your gearbox, kind of hard
to reach. This is known to misbehave due to moisture

Battery is of course disconnected doing all this. Moisture, condensation and corrosion are your enemies.Good Luck

 

I plugged in my elm scan tool to my computer & OBD Wiz was showing codes P0121 & P0193. The description for the P0121 was "Throttle/Pedal Position Sensor/Switch "A" Circuit Range/Performance" & for the P0193 was "Fuel Rail Pressure Sensor Circuit High"
The pressure at the fuel rail while cranking was 32 psi

 

First off please put your car info in your signature. I / we view so many posts it is hard to recall what car and year we are talking about.

2003 S-Type 6 or 8 ????

For the P0121 I would pull the TB plugs clean them with contact cleaner and put a little di-electric grease to eliminated moisture from being part of the problem.
For the P0193 if the pressure is good with a pressure gauge then I would be looking at the sensor.

I looked at your signature and it has listed 2003 S-Type and your post is about a 2003 xk8 You are killing me!!

This is for the plug on a XK8

Link http://www.jagrepair.com/ThrottleBodyPlugs.htm

 

2003 Jaguar XK8. I no longer have the S-Type. I'll update my signature right now

 

 

So definitely go with getting a fuel rail pressure sensor?
Also, is my signature now good?

 

Get an accurate reading first with a pressure gauge.

Go to the User Control Panel (User CP) and look to the left and go down to Settings & Options and you will see Edit Signature and type in what you want.

The people that help the most depend on this info to provide you the most accurate solution.

 

The 32 psi was an accurate reading. vance580 was with me while I was doing it. I just ordered fuel pressure sensor from Advanced Auto Parts and am gonna see how it goes