Greetings,


First time ever 'Low Oil pressure' warning came end of last week, shortly after I left the office. Fortunately just besides a parking lot and pulled in. Checked oil level and was at min. I added a quart. The warning remained on a little, at idle, eventually disappeared revving a little and gone for good. So I thought I had just been too low on oil. Today - warning came back on when starting the car! I checked the oil level again - this time, level is good. The warning would be there at idle, goes away revving a little, then back on at idle. After a few of these operations, the warning was gone and drove it a few miles back home no issue. Before asking for advice on what to consider, I do have oil leaks. At rear crank seal and timing belt cover. I have replaced the valve cover seals not that long ago. So do I have a serious enough leak to cause a loss of oil pressure? Oil pump going out on me? Cheers?

 

Yeah, it sounds like your oil pump is going out.

 

Cheapest thing first: check the oil pressure switch and maybe simply replace it... Parts like that don't live for ever... Oilpumps though normally live the entire life of the engine... Replace the switch and see then what happens...

 

Another reoccurring issue is a failing plastic cam chain tensioner coming apart and clogging the oil pump pick up screen.

You have replaced your plastic tensioners haven't you?

 

If that doesn't work, consider dropping the pan and removing the oil pickup screen. There may be pieces of plastic from the chain tensioners or guides blocking the flow.

Have you checked to see which secondary tensioners you have?

The oil warning light goes out at about six pounds pressure and the gauge will read mid scale then. So you could have low pressure and not realize it.

I see test point was quicker than me, as usual.

 

No oil pressure gauge on the XJ8!

 

Thanks all for your replies. I am due an oil change anyway, so will go the extra step removing the oil pan and have a look if anything clogging the pump pickup screen. Guess can't hurt to replace the pressure switch. I ultimately need to take care of my oil leaks at some point (I think I am going to adventure on doing the timing belts/engine front cover myself, but don't believe I am equipped to do the rear crank seal one). As to the plastic tensioner... I have always heard about this but never really known if that orange looking plastic 'flat surface' on which the chain slides on was the plastic portion referred to here, or more to the little unit.

 

All tensioners have a plastic slipper for the chain to ride on. The "bad" tensioners have a plastic housing as well.

 

You need to pull your cam covers and check your tensioners; if they have not yet failed, you are way overdue and living on borrowed time.