For those of you that may not remember, I bought Sporty, my 2003 XJ8 Sport Ed., 4 years ago on Ebay from one of those “charity car auction” places up near Chicago. They admitted it couldn’t be started, and I bought it for a song, hoping I would get lucky and find a simple solution. She is a black/black beauty. Anyway, after letting a couple of mechancis (one retired) work on her in their spare time, they came to the conlcusion it was a fuel system problem, replacing just about everything in the fuel system except the gas tank (which was cleaned out, too). After about a year or so of that w/o success, I had another “mobile” mechanic friend of mine take a shot at it, and he quicly found the problem was with power not getting to the fuel pump, for some odd reason. He corrected the problem, and she ran very nicely for about 1/2 hour before her trans. began making a horrible racket, upon which he shut her down. I then had her towed to a trans shop, who, after not being able to get her to start again, gave up (they claimed they could not r/r the transmission with another one I had bought unless the car could run). I had my most recent mechanic guy run to their shop, and he quickly concluded that a timing chain had broken during their start-up. 
So, home Sporty went until I could get up the funds and find someone I trusted to fix the timing chain issue. Fastforward another year or so … On a hunch, I let another mechanic (this one with 50+ years of shop experience) see what he thought about her condition. Earlier this week he pulled the plugs and tried to turn her over by hand. The rings were a little stuck, so he added some trans fluid through the plug holes and let her sit overnight. Last night he called me to say she turns freely and her timing is still correct = nothing at all wrong with the timing system! 
Question now is why she’s not starting. The tech is going to give her juice today and see what happens when he tries to start her. I wondered if maybe she went into some kind of “shut down” mode when the transmission went bonkers, in order to protect the engine. The tech said he didn’t think this particular model of Jag does that, but I guess we’ll soon find out. (btw, I’m still mad at that earlier tech that made the misdiagnosis of “timing chain” - that’s two years lost time that I could have been driving Sporty! )
Hi Atty,
You said she ran nicely but then the trans started making a racket. Were you driving the car at the time? Can the racket have been from the engine, i.e timing chain tensioners (secondary or primary)?
Diagnostic system’s sensing of a problems with the transmission, will not shut the engine down, but put the vehicle in “limp home mode”…
For all I know, you may already have the old girl running… As you can see, I too am struggling with a non-starter at the moment… Wanna bounce some ideas?
Kind regards,
Bard Thomas
Good timing, Bard (no pun intended) . I guess it was time to post an update:
After further exam by my current tech, turns out the two earlier techs that worked on Sporty over the past three or so years apparently did not do hardly do any of the work they told me they performed on the car, mostly r/r the fuel pump and fuel lines/filter … 
(I think I posted about this very upsetting development before, but am not sure). My present tech reports the fuel tank is still half-full of fuel that has mostly turned to “varnish” as well as contains rust. This means the car could not have actually ran, contrary to what tech #2 claimed he accomplished, at any time in the four years since I’ve owned her. I have since talked to two other persons who were present when tech #2 had claimed to me that he had got her started and running for “a half hour, before the trans. went to pieces”, including tech #2’s ex-g/f, and they verify that was not true. She did only briefly run for a few seconds once when we (tech #1 and I) tried spraying starter fluid into her intake, during which her engine sounded strong. 
Anyway, the current tech found on further inspection the reason Sporty never did run was due to a burn through of three wires (at least 2 of which are black in color) going to her fuel pump, all three in approx. the same spots. I have plans now to have the tech put in a very clean fuel tank and another good used fuel pump next week, keep our fingers crossed and see what happens. I have a hunch it may turn out there is nothing at all wrong with the transmission, since nothing tech #2 told me could be believed now.
Will update later on.
Hi,
Woaow! I’m certainly glad I am fairly technically able myself…! Not having to rely blindly on all kinds of charlatans… What they should have done, was to haul the car to a decent shop where they could hook up their diagnostic equipment to her ODB-II port.
I regret to tell you then that your current tech may not be of the right stuff either; old petrol does not turn into varnish. I once picked up a Jaguar (XJ12) in the UK, drove it on to the ferry and upon arrival in Norway, drove it from the quay and into my driveway, where it ran out of petrol. The car had over 20 years old petrol in its tanksas well as quite a bit of rust that was picket up by the sieve. I’m not saying petrol doesn’t deteriorate, but the engine will run on it.
The burnt through wires to the petrol pump should also tell you that the petrol in the tank hasn’t actually been able to prove its excellence as it never reached the engine.
My advice is that you drain the tank - if at all necessary- and mend the burnt wire (after first having verified the pumps operation by loosely connecting it with healthy wires).
After having mulled over my own issue, I have decided to focus my immediate attention to the petrol pump on the XJR. Maybe our problems are indeed identical.
Although I do post the odd question here, I am fairly technical having played with cars, and Jaguars in particular, all my life (had our first Jaguar in 1991). I am also the Technical Contact for XJ and X Type for the Norwegian Jaguar Club. You just run things by me from here on in, so you don’t have to shell out more than you have to, and that you some time soon will get your beloved cat on the road where it belongs!
Regards,
Bard
Alright, I have got a top tip for you; Check to see, when cranking, if the rev counter DOES NOT show apprx 200rpm, or if an ODB II readout says P 1336. Then you have to check/replace the Crankshaft position sensor!
I’m doing that now and expect the car to fire right up!
Bard
Edited after more careful reading of rev counter top tip…