Hi, I am quite confused with opinions regarding an issue in my W220 S320CDi. The car is with 78K miles now and is maintained by the book. 10 months ago I installed a Kleemann KD Box and did not notice anything abnormal for 2 months except for quite heavy dark-grey exhaust smoke on hard accelerations.
Later, on one high-speed long distance run I got the “1 litre engine oil top-up” reminder on the dash, which I did. However after about 625 miles the same reminder flashed. Since then if I drove gently below 75 mph, I could stretch the top-ups to about 900 miles, otherwise were 500-600 miles.
I noticed that when opening the oil cap with the engine running, there was a fairly high air pressure which could be felt some 7 inches above the filler hole.
Without touching anything, a few techies suggested that I have worn piston rings and the pressure being the result of combustion blow-bys. But then the mileage is SO LOW, and worst, the expensive dollar signs are now flashing in my poor head. Could I get advises and suggestions from members before the any dollar seeking guys experiment around with my car. Thank you.
Later, on one high-speed long distance run I got the “1 litre engine oil top-up” reminder on the dash, which I did. However after about 625 miles the same reminder flashed. Since then if I drove gently below 75 mph, I could stretch the top-ups to about 900 miles, otherwise were 500-600 miles.
I noticed that when opening the oil cap with the engine running, there was a fairly high air pressure which could be felt some 7 inches above the filler hole.
Without touching anything, a few techies suggested that I have worn piston rings and the pressure being the result of combustion blow-bys. But then the mileage is SO LOW, and worst, the expensive dollar signs are now flashing in my poor head. Could I get advises and suggestions from members before the any dollar seeking guys experiment around with my car. Thank you.
