PeachParts Mercedes-Benz Forum - View Single Post

BENZ-LGB · #3 06-13-2001, 03:10 PM

In my 1991 420SEL with 192K miles, the economy gauge rests comfortably all the way over to the left at idle. It moves slightly to the right when the A/C compressor is on. When I was having problems with the idle (sticky exhaust valve) the needle regularly moved one-quarter of an inch to the right during idle. Since the idle problem was fixed and the valve adjusted, the needle stays to the left. I don't know if this is true for all M-Bs or whether your model is a little different from the V8s. The fact that you can get a better reading at highway speed may be relevant, however.