took my 99 xj8 to a heater and a/c shop to flush the cooling system and replace the auxiliary water pump.. heater finally works and blows hot air. Drove it for 5 miles each way to work for a day and the next day drove about 40 miles..i was parked with the motor and the car jumped, thought i got hit but no one around. put the car in drive, heard grinding and felt shaking when i pushed the throttle. car went to "transmission fault" and was able to lug it home...any ideas on cooling lines being swapped on flush or what?? HELP

 

Can't imagine a link between a coolant flush and a transmission problem. Both the L/R O2 sensor harness leads are right in the area that the heater pump is located. Got a CEL? If yes, get a free code read from a local AP place. If not, probably the best place to start is with a OBDII code readout by someone with the equipment to read the transmission codes.

 

no check engine light after the fact.. would i still be able to find transmission problems through ob2 reader? never had a issue with the transmission in the 5 years I've had the car wondered why just after a shop played with it.

 

It could just be bad timing - I had that once after a car came back from it's MOT or smog test, it started acting up. Turned out to be an old (but new to me fault).

How many miles has the car done? They do have a common fault with the A drum failing. There's a number of threads on here detailing rebuild costs, rebuild shops, fitting, d.i.y etc.

If it repeats the bang/failsafe mode straight after a hard rest, it's almost certain to be the A drum..

To do a hard reset, undo the neg strap off the battery, and hold it to the pos post for 20 seconds. Redo the neg strap and try the car after letting the throttle settle.
Hope this helps.

 

i will try that hard reset..i don't dare touch the transmission at my house i haven't played with them before, and i have a hard time paying the guy i usually go to because of the cost..ive got 150000 miles on her and she still runs like a champ strong smooth shifting until the other day. the transmission was service before i got it by a jag dealer in california at about 100000 miles from what the paper work said.

 

Most of the car dealers call "service" just the normal oil change and believe me - you can never be sure that this has been properly done!

What Sean B said may be is the reason for your troubles - it's an element inside the automatic gearbox - A Drum. You can find information about it and even some photos of the broken part in this thread: https://www.jaguarforums.com/forum/x...y-money-27985/

The coolant system flush and the transmission fault is some weird game of fortune of maybe just bad luck Nothing more than a coincidence.

The most important thing you should remember - at this stage the transmission is not broken!!! It has an element which is starting to fall apart but if you stop driving the car and do the repair as soon as possible the costs for that wouldn't be so high.

I had problem with the "A Drum" mentioned above just a week ago (read my reply in this thread: https://www.jaguarforums.com/forum/x...82/#post441237) and right now the cat is sleeping in the garage waiting for its transmission repair So I understand your pain... just before Christmas Wish you all the best.

 

yes the big cat is sleeping/knocked out for winter. i think i might wait til its warm again to touch it.. my 76 blazer is doing the trick in the snow for now but has nothing on the jag. i will do my checks on all the tranny stuff going on i guess i will start with the A Drum deal i don't really know what it is but enough reading and ill have it down..thanks for the help and I'm glad I'm not the only one with a 4 wheeled best friend that roars on command.