Hey so I have a 96 xj6, the engine runs strong, 178,000 miles & my problem that im dealing with is i have a good tested alternator, & battery, but im having a drain of some sort in the car. If my battery is fully charged itll start my car perfect but while driving you see the gauge dropping and power loss happens, battery only holds power for a good 15mins. Is there a relay that I can purchase before I get a mechanic out to check my electrical? If you have had any these problems please route me to a better position.

 

Um, I know it's confusing since they put the Xj6 badge on the trunk and all, but I don't think your car is "one of ours."

This section is for the Series 1, 2, 3 Xj6s, built from 1968 to around 1989 or so.

You might more help of you look here:
https://www.jaguarforums.com/forum/xj-xj6-xjr6-x300-26/
(';')

 

Hello there,

i had had the same issue with a 97 xjr.
My solution was replacing a faulty insulator plug at the bulkhead behind the exhaust,

check out this link

https://www.jaguarforums.com/forum/xj-xj6-xjr6-x300-26/battery-already-dead-169767/#post1541552

 

Look at post #6 and you'll see a picture of where it is

https://www.jaguarforums.com/forum/xj-xj6-xjr6-x300-26/help-save-vanden-plas-early-retirement-intermittent-starting-problem-resolved-92738/