Wouldn't you know, I just joined the forum a few days ago and now I have a major problem. I sure hope you folks can help me out. I have low oil pressure at idle ( 1,000 rpm or less in park, neutral, drive or reverse, it doesn't matter).

Some background: I was accelerating to get on the freeway and reached a speed of 70 mph and a few miles down the freeway I got off. While decelarating down the off ramp, my low oil pressure light came on and the gauge hit zero (Oil pressure goes up on acceleration). Also the code P1396 poped on. I immediately babied it home and performed the following:
1. Drained the oil and dropped the pan to inspect oil pickup for any debris. There was none. No tensioner debris, no sludge, nothing. The pan, pickup and screen was spotless. Reinstalled pan.
2. I changed out the oil pressure switch with a new FAE brand switch.
3. I replaced the oil filter with the high end Puralator brand (PL15317).
4. I replaced the oil with full synthetic Castrol 5w-30 Edge engine oil.
5. I added Restore engine treatment.
I started car and the same thing happened, low oil pressure just as before.
6. Added a viscosity thickner-Rislone brand.
I restarted engine and the same thing, low oil pressure.
7. I drained oil and refilled with Valvoline 50 weight racing oil.
Restarted engine and the same thing, low oil pressure.
8. Added more viscosity thickner-Rislone and still low oil pressure.
Low oil pressure each time and the P1396 code came on a couple more times.
The timing chains, slippers, primary and secondary tentioners were all updated by the dealer (Hornsburg) about five years ago. I pulled the cam covers and inspected the secondary tensioners and they appear to be in excellent shape.

The car has been well maintained over the years and as far as I know, never abused (I know the previous owner).

I know the more obvious places to look for a problem would be the main bearings or the oil pump/gasket, but do you think o-ring failure in the VVT could cause this problem? It's easier to check the VVT or oil pump before the bearings. I guess I may have to build a smoke generator and try forcing smoke up the oil pickup and into the oil galleries. What do you folks think? I really value your opinion. Thank you!

P.S. The car has 72,000 original miles and is like new in every other respect. The engine runs perfect. No bearing noise or other unusual sounds. Just the low oil pressure problem.

 

I would get a pressure reading first.

Gus
www.jagrepair.com

 

Duh...I feel pretty stupid. I'm so upset over this I forgot the obvious. Thank you Gus! I'll check that out today.

 

Is the problem intermittent or does it always happen? Sometimes, usually every 3 or 4 weeks I get the same low oil pressure warning (no codes) during idle but usually putting the car in neutral makes it go away. It always goes away when the car is moving.

In my case I am suspecting the sensor. I've already done much of what you have and haven't found anything wrong yet. Because I only get the problem sometimes and not on every drive, I tend to forget about it until it reappears.

I haven't seen the warning in more than a month already.

 

Harbor Freight do an oil pressure test kit with various adaptors - about $26.

 

Recently, on a very cold day, at start up I had no oil pressure and the gauge would not come up even thought there was no engine sounds indicating a pressure problem. Oil level good and nothing had occurred to perhaps cause a complete loss of pressure.

At that time I discovered that Jaguar had thoughtfully installed a very loud oil pressure failure alarm.

Later in the day with warmer temperatures nothing was wrong.

Replaced the sensor and no problems since.

 

Unfortunately it's happening everyday, even on initial startup. One of the first things I did was replace the sensor and if anything, it made the problem worse.

 

Thank you batroute! I picked up one of those kits last year. I'm going to hook it up this evening and see what happens.

 

I had exactly the same problem on one of my cars(not Jaguar) a few years ago- turned out the pressure relief valve on the oil pump had stuck partially open - smallest piece of debris I ever saw but enough to hold the ball open. Not sure what system of pressure relief is on the Jaguar oil pump but I thought it worth mentioning. Good luck - let us know how you get on.

 

Ahem Tom, that was not Jaguar's low pressure alarm, that was the JagWrangler's RealGauge low pressure alarm. The oil pressure audible alarm is a feature even of the coolant only version of RealGauge.

 

Steve,

Well, that's a nice bonus! It sure is loud! You couldn't stay in the car with that ringing your ears.

Guess I should have installed both the coolant and oil pressure version but I was addressing a chronic temp problem at the time and never conceived of an oil pressure problem.

 

We get responses all the time like: Check the oil pressure, check the fuel pressure, check the compression, check the engine temperature . . . .

A tech that makes a living doing such things has all that in the big tool chest but us hobby mechanics do without or buy or rent something for a very occasional use. Want to give the wife a suggestion for a birthday present or just want to spend a few bucks take a look at these. The oil pressure gauge showed up in the never ending unsolicited email this morning with the others attached.

Engine Oil Pressure Tester Pressure Gauge Test Tool Kit 0-100psi

Fuel Injection Pump Injector Tester Pressure Gauge Test Gasoline 0-100psi

Gasoline Engine Compression Tester Automotive Test G-324 0~300psi

Vacuum Pump Brake Bleeder Tester Vacuum Bleed Test Kit Garage Tool

Nice Non Contact LCD IR Laser Infrared Digital Temperature Thermometer Gun IU BN | eBay

The auto parts stores rental programs have eliminated much of this need and of course, if I was earning a living doing this much better equipment would probably be in order.

Nothing in it for me. Just sharing . . . .

 

BTW, if you hold the button in at the end of the blinker stalk for 4 seconds, it shuts off the alarm until the car is restarted.

 

Cooper,

I had almost an identical problem on a BMW "Big Six" engine (M30). It turned out to be that the high pressure relief valve had stuck open after a little spirited driving. It was part of the oil pump. Once I took it apart, cleaned off 20+ years of grime, and re-installed it, all was good again.

I'm not sure where that valve is on our cars though. Can anybody give us a hand here?

 

Today I was finally able to do a oil pressure test on my car using a mechanical pressure gauge and unfortunately, I have no oil pressure at idle.

Thinking the oil pressure relief valve might have sum sludge or something holding the valve open, I ran some engine cleaner through the engine. It didn't help.

Looks like I'll be tearing down the engine this week or next to examine the VVT and oil pump gaskets, etc.
Hopefully I'll find the problem in those areas and not in the bearings.