Oil Warning Light flickers at 1500/2000 Revs

[stabinthedark]

Engine 200tdi, 116,000 miles on-road. Had Disco 3 months and done 2000 miles in it. Changed the oil this week, used Castrol GTD 10W-40. Before the oil change the oil warning light did flicker once or twice at low revs, but not very often

Since the oil change when engine is hot the light flickers especially when changing gear up so in 2nd at say 2500 revs and revs drop to 1500 whilst moving into 3rd gear. Oil look OK and filter was changed.

Shoiuld I be useing a different oil or do I have a problem that needs attention Just about to do a 1,000 mile return trip to France towing a trailer weighing 3250kg so I don't want a problem.

[DeanV8]

Hi there - I run a V8, so can't answer for definite but, that grade sounds a little "light" to me, for an older diesel engine, with a few miles on it. It will only get "thinner" when hot, so more likely to register low pressure.

Something you may want to check is the oil pressure switch, I have had these fail in the past, on many different kinds of engine, and start flickering at low revs when there is nothing wrong with the pressure in reality.

I'm sure someone will be along soon who has much more experience with diesels than me, and can give you a definitive idea about what to look for.

Good luck

Dean

[stabinthedark]

Solved my own problem by spending £4.29 on a new oil pressure switch which took less than 10 minutes to fit. The oil light does go on as it should when I turn the ignition on, and then dosn't flicker at low revs any more.

[stabinthedark]

Spoke too soon, just changed a rear hub bearing/seals and took Disco for a quick run. Light flickered when I slowed down and changed from 4th to 3rd. Maybe I should be useing a different oil. Managed to leave my credit card at the spares place today so I'll be back there 1st thing Monday morning and I'd better ask tham about my flickering oil light problem. There is always something isn't there!

[floyd fan]

Did you get this problem sorted? Similar problem here.

[bilge rat]

mine did the same ran it on semi synth oil, changed the pressure switch and the oil cooler thermostat, then turnd the tick over up a little, cured . alan.....

[stabinthedark]

Floyd fan
Yes I sorted the problem and thought I had posted on here about fitting an oil pressure guage. In hurry now, going sailing for the weekend. I disconnected the oil warning light cable from the sender and the light still flickers! I fitted an oil pressure guage and that shows the pressure is OK. My problem is on the dashboard or a short on the wire from the sender.

I would suggest the first thing to do is to rig a live wire (pehaps from the ciggarette lighter socket) to a small bulb and run a wire from the other bulb terminal to the oil pressure sender switch (on the oil filter housing).
Disconnect the wire that goes to the dashboard. The bulb should go on but when you start the engine it should go out and stay out. If it does not stay out then next jobe would be to change the oil pressure sender which is dead easy and the cost is not significant, think was about £10.

Ill look on Sunday night and if you have not sorted the problem Ill tell you what else I did.

Good Luck

[floyd fan]

Ok, changed my sender unit and the same thing happens. Where is the oil cooler thermostat?

[bilge rat]

iff memory is correct follow the oil cooler pipes back to the oil filter housing, its behind one of them, think its the one 90 deg from the engine. its a while since i did it. alan....