Flickering oil light

[twhedbee]

The oil light on my 2002 Disco (175K miles) started to flicker about two weeks ago. The light would flicker on after the truck was well warmed up, just as I applied gas after idling. I took it to a local shop immediately for an oil pressure test. The results were:

Not quite cold, but only slightly warm
Idle, in park - 22 psi
2000 rpm - 44 psi

Well warmed up
Idle, in gear - 14 psi
2000 rpm - 42 psi

Mechanic replaced the oil pressure sender after completing the test. I asked my Land Rover shop about the numbers. While not perfect, they felt they were reasonable for a truck with 175K miles. I drove the truck for 10 more days without the light coming on at all, and that led me to believe it was, in fact, a faulty sending unit.

This past weekend, I left my truck parked at the airport for 4 days while I flew to LA to see my daughter. Wouldn't you know, when I drove home from the airport last night, the darn light started to do the same thing -- flickered on after applying gas from idle.

Now I'm really confused. Do the test numbers seem satisfactory? If it really is the oil pump, why did I go 10 days without a blink after replacing the sender?

Any thoughts would be greatly appreciated. I'm worried about the truck's health and longevity.

Tom

[Bosnian Discovery]

You may just have cracked or broken oil pump gears that are failing intermittently. When the gears go (and they go OFTEN) you can either get a catastrophic loss of pressure, an intermittent dip, or more often there will be no symptoms at all minus a light clicking. The gears aren't very difficult to replace and kits are available from Atlantic British and BPUtah so it may be worthwhile to get it sorted out. Since these are about the only parts that can fail in your oil pump, they're a much better investment than $600 for an all-new unit.

[Disco Mike]

I agree, the outer gear ring is probably starting to crack.
If those number are good, then I would suggest you pull the front cover and inspect/replace the pump gears.

[twhedbee]

Thanks, guys. I'll try to post updates as they occur!

[Disco Mike]

Don't drive it in the mean time or you could trash the engine.