Fuel Gauge Not Reading Correctly?

[GregE240]

Been happening for about two weeks now.

After a fill up, I noticed the gauge go right up to full, then level off at about three quarters. At first I thought I hadn't tanked it, but given I got nearly 400 miles out of the tank and about 63l went back in I knew that wasn't the case.

Since then subsequent fill ups have only taken the needle up to 3/4 apart from last night when it went back to full again. Momentarily. Then it fell to 3/4.

I seem to recall reading about the sender in the tank going south on some models - does a '98 W210 fall into this category as well?

I can't honestly think of what else it could be. Any ideas, chaps?

 

[djcheung]

I have a 98' W210 and the fuel sender unit was replaced just over a year ago under RAC warranty.
It would not register a full tank even if the tank was full and sometimes the gauge dropped by a quarter tank for no apparent reason.
I did take the car to the dealer more than 5 times to convince them there is a problem with the sender unit before they agreed to replace it under warranty.
Hope this helps!

 

[rirhill]

Greg
Mate I have had the exactly the same problem. When I finally got a date from the dealer to take it in, I filled up at Safeway the night before so they knew it was completed full and low and behold the needle moved about a bit then settled on the full. I normally fill up at Sainsbury's for ease.

I have spoken to MB and they know about it and its apparently the additives they put in the petrol. There are quite a few threads about it so it is common.
If you still have warranty they will replace if you keep on at them.

Good Luck
Ian

 

[robert.farmer]

i have an old 1990 200te, i can put £40 in and the needle hardly moves, just have to keep it topped up

 

[GregE240]

Thanks Ian (your siggy pic doesn't show - seem to recall it was the one taken at Silverstone or Brands? Not sure if its my Internet link here)

Sadly its out of warranty and I'll have to stump up the brass for it - anyone got any idea how much supply and fit these things cost?