95 xjs 4.0 : I'm hearing what sounds like loud lifter noise chatter on start-up, noise does get quieter when warm. when stopping at light or stop sign pressure drops and low pressure light goes on. Giving it gas and the light goes off. pressure gouge is erratic. when I test what what should the pressure gage read hot or cold.
Please help with possible causes

 

How many kilometres/miles are on the vehicle?

Is the engine oil level correct?

Generally, low oil pressure at idle is an indication of worn rod/main bearings.

 

You need to get a good test gauge in place and measure the actual oil pressure. Lifter noise and low pressure light could be related, even could be impacting chain tension so you really need to get on top of this and soon - not sure I'd keep driving it.

I'd expect at least 10 to 15 psi at idle even hot - I think the light comes on at 7, 40 to 60 at normal road speeds > 1500 or so rpm - although I've no personal experience with the AJ16 that would be the ball park I'd expect

 

Richard,

The noise after startup could be the known tensioner problem. See the attached Jaguar Service Bulletin.

As regards oil pressure, the 4.0 engine runs at a much lower pressure than many owners expect. Jaguar state 40psi (2.75 bar) at 2000rpm.

As regards the gauge being erratic, it's naturally supposed to vary at different rpm and temperature. However that seems to confuse some owners. As a result of US owners complaining that the gauge varied, Jaguar decided to try and avoid the complaints by fitting a revised sender that just pinned the gauge at the 1/2way position unless the pressure was really low. It sounds like you have one of the original senders (which imo is a much better one to have). However, it could be that it's reading incorrectly. I would start by checking the pressure first with an external gauge and then assess the situation.

Good luck

Paul

 

Duplicate

 

There are 65,000 + -
yes oil level as on dip stick is correct
I will check pressure, if it is low ,what should I expect to pay for rods /
bearings thanks for your help !

 

Richard,

Don't even start thinking that you might need a rebuild. AJ16 engines are almost unbreakable. It would have to have been severely abused to have worn out the bottom end, and I'm sure you haven't done that! I've never heard of an AJ6 or AJ16 engine that wore out it's bottom end.

Get the oil pressure checked and let's see what it is.

Paul

 

@Richard Portale, if the oil level is correct, then as others have suggested, use an external gauge to determine actual oil pressure. Post the readings here to determine if there is truly a mechanical fault with the engine.