Hi,

I adjusted my valves recently on my newly acquired 1980 240d 4 speed and noticed 3 valves were extremely tight.

The car is fairly low mileage with around 120K miles.

I notice a slight dance of my oil cap at idle, although it got better after I adjusted the valves. It is not terrible or overly concerning to me because it starts right up and stops the same way. Runs with plenty of power.

However, I am thinking that the car was driven awhile with the tight valves and was wondering if there is anything that I could add to the oil that may help burn off carbon that may be causing the oil cap dance (this is my 3rd diesel).

I want to get ahead of this to keep the engine healthy just in case there is any buildup of carbon.

Thanks.