big83bronco

When my car is cold it has good oil pressure (on the "1" @ idle, raises to "3" when above 1500rpms) once the car goes to normal operating temp, the guage reads "0" @ idle but builds up to "3" as soon as it comes above idle.

Why would this be? It doesn start tapping or anythign when the oil pressure drops, could it just be the guage being stupid?

adn btw the oil level is good, just changed the oil too.

myfirstbenz

Are you using the right weight of oil? I know that my guage behaves differently depending on that. I just changed my oil and timing chain and used 10-30 because it is well below freezing right now. Started my car today for the first time this week and it was 13 degrees, damn cold. My oil guage stays around 1 at idle when warm, and at about 3 when cold.

When is it going to warm up? We are getting an arctic winter here in WA, and it sucks.

big83bronco

Still very warm here in Georgia, it was 76 deg. Farenheit. yesterday. Anyways it has 20w15 in it, whicj is what the dealer put it it from new according to the service record book.

big83bronco

Do you think maybe its a problem with the sender? I cranked it up and at idle when warm you can see plenty of oil being injected ontop of teh camshalft, so I do still have oil pressure at idle, just the guage says "0" at idle once warm.

shadowgriffen

I use 15W50

reads 2.5 when cold at idle (always shoots up to the three with increased rpms)

reads 0 when warm at idle (always shoots up to the three with increased rpms)

big83bronco

I dont feel so bad anymore, that just isnt a good feeling looking own at a stop light and you have "0" oil pressure.

shadowgriffen

LOL I totally hear you. When I first bought the tank I was like WTF????? then I statted looking into it and it seamed I wasn't alone

kwb210

I believe MB reccomends 0w-30 5w-30 as the correct oil. With the MB engines all clearances are VERY tight compared to american engines so the engine needs a thin oil at startup. I use the Mobil 1 in 5w-30. Anyone have a manual handy to check it out?
kurt
1993 300 CE

mgw_300e

It could be your sender or it could be the lower wiring harness.

myfirstbenz

I'd check your owners manual there. I'd go outside and look at mine, but it is too damn cold and icy out there. I use 10-40 most of the time and sometimes 15-50 in the summa time, but if I remember correctly the manual says 10-40, and my brothers CE dipstick actually has 10-40 on the plastic handle.

Oil is such a tough call, it's like the battle of the antiacids, in the end they really all get the job done, although I did find a economy improvement when I used synthetic, and it is so nice and clean.

shdoug

Interesting. I've never seen mine below 2 bar (30 psi) with the engine hot. Also, looking at pics of these cars on E-bay, some are shown with the engine running and warm and they are all at 2-3 bar. However, if you see oil at the cam you should be OK. The cam is the last place the oil goes, I believe. Low oil pressure can be due to loose bearings, worn oil pump, or a pressure relief valve stuck open. All are major repairs so as long as it comes up when you are driving I would not worry about it. I had the identical issue with my '85 Volvo turbo. There were never any noises or problems associated with it. BTW, my stealership uses Quaker State Peak Performance 5W30.