Well, during our lengthy trip to B.C., my fuel gauge seemed to be on the blink. Not wanting to drop below the one third remaining mark. I assumed the "second" sending unit was sticking, and found that replacing both units on a W202 is a $600 proposition.
At one point, I had driven 550 km's, and the gauge was reading 1/3 gone. Than I put 39L in. 39L is WAY more than 1/3 gone. More like 1/3 left.
Anyway, due to that, I have not been trusting the gauge, and topping it frequently.
On Monday, we went to Calgary and back. I stopped at Red Deer on the way home (at about 500 km's showing on the trip odo) and put 12 litres in, just to make sure I would make it home.
Well, I got home, and sure enough, the gauge was reading 1/3 remaining. So, now I'm curious as heck. What will happen? With 700 km's showing on the odo, I fill a small jerry-can with gas, and drop it in the trunk.
After two days of errands and 150 km's more driving, the gauge has been reading MOSTLY (see below) normal. At 850 km's showing, it's at 1/8 of a tank and looks like the light will come on soon.
One funny thing it does is go up a little bit after driving the car a few minutes. Not much, but a little. Can't say it hasn't always done this, as I've never paid such close attention to that little needle before. Sloshing? Expansion?
So, maybe the gauge is working properly, but somehow my car's fuel economy is better? (850km's on the 55L +12L top-up is 7.9L/100km's or 30.5 MPG US) That mileage is not unusual for the highway, I might get even higher, but not for the 140+ km/h pace that Highway 2 from Edmonton to Calgary sets. Usually, I get much worse at those speeds.
So, now I'm in a quandry. The gauge SEEMS to be working properly, but I'm still a little unsure of trusting it. Okay, I'm a paranoid nut, but I KNOW the majority of you are, otherwise what the heck are you doing reading this?
I don't want to drop $600 for new sending units 'fer nothing. The dealer has indicated no way of testing them without doing all the labour of changing them out.
My thinking is that I'll run a few more tanks through and see how it does, but I HATE it when I think something might be wrong with my car. You leave one thing, and then another comes up later, and then you leave it too. Before you know it, the car is rolling junk like 90% of the cars on the road.