Oil Pressure Question
 

What should be the normal oil pressure reading, at idle, with a warm engine for:

1. A 420SEL (91)

2. A 300TE (89)

I am not having a problem with either car. Just curious.:confused:

Thank you.

Don't know if your 300TE has the single or dual cam engine.

Mine has the single cam version. Once fully warmed up, the tach reads 1 BAR using conventional 10W/40 oil and either a Hengst/Mann/Mahle-Knecht oil filter. On occassion, it will dip a hair below 1 BAR.

I would not be comfortable with a reading of less than .75 bar (in my opinion). My manual states the following:

Idle >= 0.3 bar
3000 rpm >= 3 bar

Dont worry about low oil pressure. As the oil warms up, the oil exapnds and thins out. In my 99 S420, my oil pressure was around 1 at idle so Mercedes changed the oil pump and sending unit. At startup the oil pressure shoots up but it then slowly decreases as it warms up. I was told it is normal.
Like me, I see you're in So. Cal., using a heavier weight oil will prolong the oil pressure but eventually it will thin out. I have a 300E, and I used 5 bottles of Chevron 20W-50 and 1 bottle of Mobil 1 10W/30 w/ a Mobil filter. During short trips for 15 min, the lowest I read is 2 bar but after traffic of the 101-405, it goes down to 1. If you oil pressure does not jump to 3 during acceleration, then you might have a problem or you need an oil change. Relax