oil pressure issue

Hey chaps and chapesses.
Fitted my vdo gauges today and they're all working hunky dory.
However, i was always under the impression that oil pressure increased slightly as the engine warmed up? My gauge from cold, at idle shows between 3-3.5 bar. When its warmed up, this drops to around 0.5-0.6 bar at idle. When driving the pressure is around 1-1.2 bar. Now i'm beginning to think i may have a motor issue. Surely the
pressure should be higher than this??
I've got a new oil pump…is it worth plonking that on or is it likely the engine is worn in general? Its got 137k on it.
Any help/advice greatly appreciated…Nearly forgot, engine is the 1.8i dx.

Oh…and my low oil pressure buzzer doesn't work. The light flashes when i take the low oil pressure wire off(think its blue or brown from memory). Can anyone tell me where the buzzer is so ican replace the bloomin thing?

no its the other way round, the colder the engien the thicker the oil hence higher pressure

0.5bar is fine, the threshold for the warning lamp is 0.3bar at idle when hot. also the buzzer only goes off if pressure drops below 1.8bar @ 2kish rpm, this is handled by the white switch in the filter housing. the low switch on the side of the head only controls the light at idle.

Thanks RJ….spent some time on it today and i've got good pressure now.
Fitted new Febi oil pump that ive had lying aroung for a month or so, also done other little jobs: Oil and filter change, plugs and plug leads, and changer my senders round a little, i'll explain.

I've now got the 5 bar vdo twin post sender fitted to oil filter head with a T piece/banjo.  I've also got the mfa oil temp plugged into the same t piece. No change to the high oil pressure sender, still on filter head in rear hole.
I've also got an oil temp sender in the location where the low oil pressure sender was, on the right of cyl head. Low oil pressure sender not needed as taking that feed from the 5bar twin post sender fitted to filter head.
Sooo…things look a lot better now, due in the main to the new pump.

ah those figurees were a bit low for the filter housing, I assumed you had replaced the sender on the side of the head. never mind its all good

Thanks for checking back RJ. Its all good now….i've more gauges than i know what to do with. In fact i reckon the car is probably 0.25 of a second slower to 60mph, due to the extra weight..!!   

everyone loves gauges

rubjonny said

no its the other way round, the colder the engien the thicker the oil hence higher pressure

0.5bar is fine, the threshold for the warning lamp is 0.3bar at idle when hot. also the buzzer only goes off if pressure drops below 1.8bar @ 2kish rpm, this is handled by the white switch in the filter housing. the low switch on the side of the head only controls the light at idle.

Mine are not connected to anything both are unused, if you could help out here an tell me where they should be wired too and I assume a pair of oil gauge's?

I just install a set of oil gauges and then wire them directly to each pressure gauge?

I've noticed my buzzer comes on every now and again, usually when I hit a pot hole it will just turn off!
Could this be related to why my engine only runs for a few hours and then will not re-start for a few hours, even if this was the case and I installed oil temp gauges how would this stop an oil over heat? As the engine seems fine running around and the water temp is only hitting the half way mark?

Kind regards,
Didge

f you mean the pressure switches, you hould have a brown or blue one in the side of the head, and a white one in the filter housing. the filter housing one will have a blue/black wire, the one on the head is yellow (wire colours might be swaped on a later model) these wires run to the dash where they supply the oil pressure warning circuit.

if you want an oil gauge you need to fit an oil pressure sender, the ones on the engine now are just switches.

with the buzzer it could be the old wires are flopping about in the bay and shorting out from time to time.

your engien start problem is unrelated I expect, the dash should run about half way when engien is up to temperature so all is well there

rubjonny said

f you mean the pressure switches, you hould have a brown or blue one in the side of the head, and a white one in the filter housing. the filter housing one will have a blue/black wire, the one on the head is yellow (wire colours might be swaped on a later model) these wires run to the dash where they supply the oil pressure warning circuit.

if you want an oil gauge you need to fit an oil pressure sender, the ones on the engine now are just switches.

with the buzzer it could be the old wires are flopping about in the bay and shorting out from time to time.

your engien start problem is unrelated I expect, the dash should run about half way when engien is up to temperature so all is well there

Thats the ones rub I think it's a brown one on the side and a white one ontop (filter housing), Right I'll see if I can wire these up into the dash over the course of a month or so.

Cheers rub your a star matey!
best regards,
Didge