Hello!

I have just recently purchased a 1997 Disco. Runs great, even with 150K. Changed the oil as soon as I got it. Rotella 5W-40 w K&N 3001 oil filter. Also did the rear brakes (new rotors/pads/blahblahblah), bled the front and rear brakes.

Changed the power steering fluid along with the coolant.

We are still in the process of bringing this truck to current before I start driving it more often. The previous owner didn't do much off -raoding with the truck. He used it as a daily driver. It's never been off road. Diff lockers work.

Only problem that we seem to have now, which seems to be a common issue with Disco's, is a flashing oil light at an idle, only when the truck is very warm. As soon as I hit the gas, the light disappears. I know oil pump issues were common in 03 and 04 Disco's, and not soooo much the DI, but, ya know, anything can happen.

I was hoping for some advice? Could it be the pressure sensor acting up on me?

Thanks

 

It could be, and is cheap. Buy a new one and swap out. At the same time you are doing this you can use a mechanical oil gauge to test PSI, to be sure the sensor is bad and not the oil pump or oil cooler (restricted) or oil pickup (coated with sludge).

IMHO you should park the truck until this is resolved. The switch resets around 7 PSI. If it is telling the truth, you have other problems. Would be bad to be driving around with only 9 PSI of oil pressure. My D1 with 183K makes 44 PSI hot at RPM and 18 - 24 at idle. 44 at idle cold, which is expected because filter bypass is engaged with cold thick oil.

You could also be overheating, so don't go by gauge, plug in a scanner (rent/borrow) or an ultra gauge and get digital readout of coolant temp. If you were at 247 degrees F that would be bad as well.

Two wear items come to mind on low oil PSI - main bearings on the crank (write up in tech area for in-truck replacement) and rocker arms for the valve train, when worn they can knock down oil PSI as well.

 

Rotella 5W-40

I would be willing to bet the problem is the 5w40 oil.

5w anything is too damn thin for these especially with higher milage and higher temps.

15w40 20w50 or straight 40 weight would be a much better choice.

Rotella is fine but you need rotella 15w40 or Castrol GTX 20w50. So drain that 5w and put in onme of the above before you screw that motor up.

 

Its not the oil pump or the sending unit.
It is either the idle speed is to low, oil is to thin or the bearings are to worn.
Drain the oil, fill it with 15w-40, see what happens.
Make sure you are adding 7qts of oil as thats what it holds.

 

Drop the oil pan and clean the pickup screen.

 

WINNER WINNER CHICKEN DINNER!!!

I totally forgot about that one.

 

And if you do it right you can use the 5w in the lawn mower/anything yard related.

 

LOL.......

I personally don't think the 5w-40 is hurting anything. It's still oil and that's better than none eh.

I'd like to correct oliver's statement that the truck hasn't done anything, just been a daily driver........must not understand that's huge accomplishment. Rookie statement.

 

The 5W40 T6 Rotella is just as viscous as the the 15W40 Rotella or other 40 weight oils when the truck is warmed up. And if it is flickering the low oil light at idle, and idle is around 700 rpm, it might not be making 30-40 at 2500 rpm either. PSI test is a good thing to do even if all you do is pull the pan, clean the screen, replace the O-ring on the pickup tube, and loctite the pickup tube bolts.

 

Thank you very much. I will definitely do the PSI test before going about changing the sensor or anything else. Until then The truck is staying parked.