My 1996 Jag xj6 was working fine until I stopped for gas. When I left the station, I stepped down on the gas to quickly accelerate to highway speed, the car would not shift out of third gear. Now it starts off in third and stays in third. I don't think it is even starting in second (in Normal Shift Mode) and it won't start off in first gear in (Sport Shift Mode) Can anyone give any suggestions on what broke or came loose and where the shift cable or vacuum lines are located? I had a 1990 Pontiac act similarly and it was a vacuum line that came lose. I had a 1987 Ford van E150 that had a similar problem and it was a shift cable that broke. I don't know that much about the Jag yet, but I guess I'm going to have to learn. I am sure I can fix it the issue if I can only find the problem.
Any help is appreciated.
Thanks,
Terry
feel free to e-mail me: terryhume-ctr@centurytel.net

 

Sounds like your transmission is in default or limp mode (insert Anthony Wiener Joke here). Electronic Transmissions of that era read many parameters such as the input speed, output speed, gear ratio, line pressure and temperature, solenoid resistance etc. If the TCU detect a discrepancy in one or more of the parameters it goes into limp mode. It could be something simple like a failed PWM solenoid or it could be serious like a slipping clutch pack.

Check the basics....
Check the fluid level, check the electrical connection to the transmission, check the fuse. If all that is good try disconnecting the battery for 10 min and if it still doesn't work you'll have to consult a transmission professional.

 

I did as you suggested. I disconnected the battery and while I waited, I checked all the fuses I could find. OMG Jaguar put fuses EVERYWHERE! Under the hood, under the back seat, in the trunk. Gee, Jaguar must have part ownership of a fuse manufacturing company! Anyway, no blown fuses. I reconnected the battery and now the car shifts through all the gears just as it should. A BIG THANK YOU for the help!

 

Good and quick sort Terry.

Might pay to remember your XJ6 is known in Jaguar world as an X300. Confusing, of course it is, but you will get used to it.

Also bear in mind that if the reason it went into limp mode in the first place is still there, it will happen again, or maybe not, it is a sensing thing as said previously.