Low oil pressure

[AlfaJack]

I was sat in traffic on the M25 (didnt take long Rolling Eyes) engine was ticking over at at its normal 850 odd rpm, water temp was 93C with the fan kicking in and out as it should, but the oil pressure was under 1 bar, the oil pressure light kept flicking on and off, I gently reved it to 1500-2000 rpm and got about 2.5 bar of pressure up which is ok and when driving normally I have about 4 bar (btw, on a cold start iv got over 7!)


Should I do anything? I have changed the oil and filter within the last two thousand miles, am I going to need a new oil pump?

[Steve Webb]

I'd check the operation of the sender first, could be its giving a false reading at lower pressures. So long as the car isn't using anymore oil than normal and the sender is ok, then yep i'd start to look at the oil pump.
What temp did you oil get up to? And what sort of oil are you using, Brand/SAE

Hope whatever it is, its not too serious.

[AlfaJack]

Hi Steve,

I am running 10/40 semi syn, Comma oil.

Fletch advised me to use 10/60 Motul like you do, next change I will do this.

Not sure what temp as the gauge is broken :oops:

[Steve Webb]

One thing you might want to check, oil only gets diverted through the oil cooler once a thermostat opens. If the thermostat is bust, then the oil might get very hot, and as you are 'only' using 10/40 then it might thin out too much.
Not sure how likely that scenario is, but you might want to have a feel of the oil cooler next time you get the car fully up to temp to see if its hot.

Steve

[Juan AR155Q4]

btw, on a cold start iv got over 7!


Over 7? I can´t pass over 6, I thought the over pressure valve was set on 6.

As Steve said, I´ll check the sender. In my case, with hot oil, I have less than 1 on iddle but none of the warning lights turns on. Reving the engine, reaches normal pressure (4@3000).

[Negative Creep]

mine's always on 3/4 when cold and about 1/4 when hot, which ive been assured is normal

[Brul(tm)]

When cold, the pressure is 8 bar or higher, meter stops at 8 :shock:
When the engine and oil is on temperature, i got just a little above 2 bar on idle. While accelerating the meter shows max 7,5 bar.
Need to say that the pressure is a bit modified, and that's up ;)


Greetings,
Marc

[Juan AR155Q4]

Really high pressure. What have you done to your oil pump?

[arjunior45]

Need to say that the pressure is a bit modified, and that's up ;)


I also would like to know what have you done with the oil pump.
Illuminate us please.

Nick

[Juan AR155Q4]

Up with this!!!

Alfajack, did you solve this?

I'm having same problem and the next to do it's an oil change. I'm going for some 10W60, and hopes that solve the problem.

[AlfaJack]

Hi Juan,

I have not done anything, the problem has not yet come back but the weather has been cooler since this time :? :?

[Juan AR155Q4]

:(

I was hoping to find the solution...

I'm really worried about this. With warm engine I'd really LOW pressure (almost 0). And warning light isn't working.

My temporary solution is keep it in revs, but it's really a pain to do this in each stop light.

I'll try an oil change.

Could be the oil pump? With the engine revving I've good pressure (4bar@3000rpm).

[AlfaJack]

Same here but its dropping to 1 bar now.

Its possible the sending unit is just old and needs replacing to get a proper figure :?

[Juan AR155Q4]

This weekend I'm going to try an oil pressure gauge I have, but really don't think is a sender problem.

I'll update.