Anthony Galioto wrote: > I took a small trip about 125 miles of highway driving at 65-75 mph. > The car is a 1983 240D with 63,000 miles on it in good condition. It > was a hot day 83+ degrees. After exiting the turnpike and stopping for > a light, I noticed that the oil pressure gage was fluttering on or about > the number 2 on the gage. It normally stays on the 3 which is the max > when at idle in local driving and at idle. The water temp stayed on a > constant 80C highway and local driving. The fluttering is in concert > with the rhythm of the engine.
If the engine RPMs are varying, even slightly, the oil pressure will follow them. 2 bar is perfectly acceptable at idle; it's normal for the pressure to go down a bit as the engine warms up. I think Marshall said the minimum is 0.3 bar at idle.
