Anyone experienced this? I have a 98 ML and after receiving the fuel system upgrade (pump/sending unit, fuel lines, pressure regulator), the fuel gauge is off. With that I mean on a full tank of gas (it reads full on the gauge), the gauge will start dropping to about 7/8 after <10 miles of driving. It will go down to 3/4 after about 20 some miles and now it's sitting on slightly above half with 55 miles driving. I know it's off because when I refuel at half tank (as shown by the gauge), I could only squeeze in about 6 gal. The dealer already replaced the new pump/sending unit once, and it's still doing the same thing. The original pump/sending unit wasn't doing that, it was accurate down to the last few gallons.
Any suggestions.

Thanks
steve

Why was the fuel pump/sender unit replaced if it was reading properly?

If they just replaced all of that then I'd just take it straight back to the dealer and get them to sort it out. If everything has been replaced then there is no reason why there should still be a fault.

__________________
Alex.

MB Tech
Sydney, Australia
Volvo 122S
W201 190D 2.5 manual
W202 C240
W203 C32

Well few weeks ago, I asked to change out the original fuel filter and got MB to partially pay for the whole fuel system upgrade. While the dealer opened up everything, they replaced the fuel pump/sending unit as well since it's covered by MB's goodwill. So all is good except that the fuel gauge drops like dow jones. I took it back one and they replaced the fuel pump/sending unit already. I was just trying to see if anyone had similar experience and can share what the dealer did to fix it. I will let it drive for few more tanks of gas to see if it will magically heal by itself.