BOERNE ML320

We recently embarked on a road trip of roughly 1000 miles. The trip went off without a hitch. We took the opportunity to check the gas mileage. The first leg was early AM and moderate speeds of 70-75 MPH. At our first stop we fueled up and calculated the MPG at 22.1! Later in the day the air temp was close to 100 and we were running about 80-85 MPH and our fuel economydropped to 20.5. We noticed that the first 1/4 tank was used up quite fast and the remaining fuel (according to the guage) went down at the rate one would expect.

On the return home we gassed up with about 1/3 tank left. We started the truck pulled 50ft. into a burger joint, had lunch and got back on the road when we noticed the fuel guage had not moved off the 1/3 of a tank where we started. So we drove a while thinking "did we get gas?". We drove a ways down to the next available Shell station and attempted to fill up again. It would only accept 1.5 gallons. I was confident that we were topped off. The guage kept dropping as gas was being consumed until the amber reserve light lit up. My wife insisted we get some gas and we filled up again. This time only accepting 7 gallons of fuel. Turning the truck back on the guage registered a full tank.

Has this happened to anyone?

Over all we had a very pleasant roadtrip experience with our 2001 ML320.

Benz_nut

Sounds like your fuel guage sending unit is going out...it's a DIY job or you can take it to your dealership to fix it under warranty...

Mine did something similiar like reading only 3/4 full when the tank was full, then when we came to stop lights, it would jump from half a tank to a full tank then down again...

BOERNE ML320

Do you know of any DIY write ups on this subject?

Wolfgang

Here's one linked from this page:

http://www.whnet.com/4x4/badgas.html

PaulX608

If you search the forums here, you'll find plenty of our experiences with this. It's not a highly technical DIY, but it's plenty tedious.