XJ40 runs for a mile then engine loses power

XJ40
1

1990 XJ6 only 15800 miles from new ran fine down motorway for 60 miles.
Next day stuck in traffic. Everything still ok.Then short run engine loses power as if in a default mode except car eventually runs to stop.Leave for a while,engine runs up to 800 rpm then throttled up to 1500 ran there for a short time then engine rpm falls and stalls.Same story repeated as I struggled to get her home( down to 5 mph) and then stopped restart etc
Feels like fuelling replacing fuel filter,probably never been changed in 28 years.Where is the drain plug for the tank,only one tank.

2

XJ40. I moved your topic.

David

3

Edward,
You are on the wrong list. Your model is newer and very different from the Series I, II and III XJ6s and XJ12s discussed on this list. Although your car is badged as an XJ6 you model is often referred to by the internal Jaguar code name given to it, XJ40, because it is so different from the earlier cars.

I recommend that you try posting to the XJ40 list.

Paul

4

Paul, you should copy that text somewhere so you don’t have to type every time. Should we ask Andrew to put something clearer in the description, on the web page?

David

5

There isn’t a drain plug for the tank AFAIK (at least my 94 doesn’t have one!)

You can change the filter first to see if that makes a difference, the filter is under the sill just ahead of the LH rear wheel. Filters are quite affordable and easy to change.

If the filter doesn’t cure the problem, you might want to check the fuel pump operation.

6

Thanks for that info,now posted on the correct page.

7

=Larry thanks for that a job for tomorrow.
Might be interesting to cut the old filter in half and see how bad it is ?
Ed

8

I’m not sure it would make much difference, but I’m open to suggestions.

9

Note a new thread was opened on this subject -

https://forums.jag-lovers.com/t/engine-runs-and-car-drives-for-a-mile-then-problems/367403/3

10

I posted my Xj6 problems on the wrong page it’s a1990 3.2 so here goes .
Bought this car and ran it home over 60 Miles ,no problems.
Next day spent some time in traffic,car didn’t overheat but eventually went into what I thought was default mode but eventually lost all power.
Switching off then restarting gave me a short respite but same problem.
Limped home.This feels like a fuelling problem I will start with a new filter.I have been advised there is no drain plug on this model which has only one tank.The car has been stood for a long period as it’s only covered 15900 in 28 years so I guess there will be stuff in the tank.
Let the forum know the eventual outcome.

11

A 1990 XJ40 with a 3.2 engine?
What is the last six of the VIN on your car? If post VIN 529285 then it is a 1991 model (irespective of when it was first registered), the first year that they fitted the 3.2 litre AJ6 engine to the XJ40.

The model year is important - particularly in respect of the fuel system because in 1991 they fitted in-tank fuel pumps to replace the troublesome external pumps on the earlier models.

If you suspect a fuel problem, best to check the fuel pressure at the fuel rail - should be around 35 / 40 psi for the engine to run smoothly. http://www.jag-lovers.org/snaps/snap_view.php3?id=1357201999

This is the sort of kit you will need - http://www.jag-lovers.org/snaps/snap_view.php3?id=1076076938

12

Bryan thanks for that it is 3.2 registered in October 1990.
I will start with filter first and then progress up the line.
Much obliged.

13

I have now succeeded in acquiring the correct fuel filter,quite a small one compared to later models.Unfortunately the filter use aluminium type nuts which easily cross thread . I decided to try and blow through the old filter with my breath which was almost impossible but not so with the new one.
No wonder the fuel cannot get through. So will report soon to see if it’s cured the problem.
XJ40 1990 3.2