Recently purchased a 2004 XK8 with 80K mi. Wife finally let me drive it today and I noticed an engine surge while at a steady cruise speed. Only a couple hundred RPM but noticeable. Common? or indicative of some thing needing to be addressed? Also, is there an accessible port to get a direct oil pressure reading? I don't like the way it sounds on start-up and wanted to see how quickly the oil pressure builds. Thanks in advance.

 

There is an easy way to get the oil pressure, and even better, the actual temperature instead of that idiot light disguised as a gauge. Go to thejagwrangler.com and check out Steves' Realgauge kit. Oops, I forgot you have the nav unit, you would have to replace that with the 3 gauge panel to get the oil pressure.

 

As to the surge:

Was it while cold? And at about 40mph? Does the surge go away after the car warms up?

This seems to be an affliction of the early 6spd transmission programming. There is an S-type TSB about flashing the TCM with the latest software and then doing the transmission adaptation cycle.

 

The OE Jaguar oil filter has a non-return valve to prevent oil draining from it back into the oil sump when the engine isn't running.

Some aftermarket oil filter brands that 'fit' don't have this non-return valve. Consequently it takes longer to build up pressure after start up.

Worth a check to see what type is fitted.

The first thing I do when I get a new (to me) vehicle home is an oil and filter change. I like to know exactly what is in my engine!

Graham

 

If you hear a clack clack clack from the fron of yiur engine most likely the timing chain tensioners could be about to fail. Mine made an awful noise. Primary tensioner failed and made the guide slack. You could hear the timing chain smacking around.

 

Whilst a not infrequent occurrence on a 2001, it would be very unusual on a 2004 4.2 litre.

Graham

 

This is true I forgot they changed the tensioners.

 

Thanks everyone, correct oil filter installed, know now how to do the oil gauge, will check with the dealer about the re-program for the trans to see if it applies to this one. I think 2004 was the second year for the six speed. You would think they would have sorted out any problems by then ?

 

But you can never ignore what the PO has done in the intervening 10 years!

Graham

 

Does it sound like the engine picks up on the revs then settles down again but you do not actually go faster or slower?

Quite common on the 6 speed and the TCM reflash only sometimes works, if it does not cure it then a new torque converter is required