Fuel gauge drops to 3/4 after driving 10-20 miles from a full tank
Thread Starter
Member
Joined: Sep 2009
Posts: 97
Likes: 10
18 Model X, 13 GL350, 13 Odyssey, 07 530i
Fuel gauge drops to 3/4 after driving 10-20 miles from a full tank
2004 ML350:
1. Fill up the tank to the max.
2. The fuel gauge shows it full.
3. Drive around 15-20 miles.
4. The fuel gauge shows 3/4 full.
5. Once it drops to 3/4, the gauge works normally.
What should I check?
I put key to ignition position II and removed & plugged back in Fuse 5. But I think this works when the fuel gauge somehow drops to 0 when the tank is full, which is a diff problem.
1. Fill up the tank to the max.
2. The fuel gauge shows it full.
3. Drive around 15-20 miles.
4. The fuel gauge shows 3/4 full.
5. Once it drops to 3/4, the gauge works normally.
What should I check?
I put key to ignition position II and removed & plugged back in Fuse 5. But I think this works when the fuel gauge somehow drops to 0 when the tank is full, which is a diff problem.
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
This problem usually occurs because of a faulty float which is part of the fuel pump.
Wait until the tank is 1/4 full and remove the fuel pump. Clean the grid with a pencil eraser and reinstall the pump and hope for the best.
Ordering a new locking ring prior to the job is necessary.
Member
Joined: Dec 2010
Posts: 88
Likes: 18
2015 S550
I don't recall needing anything special for it. I did reseal it with some caulk to make sure no fumes came out (it had been sealed before). In my model they changed the pump, added a whole additional hose, changed the filter,... so it was much more of a project than just swapping the pump. Hopefully you just have to replace the pump which is easy.
I do recommend running the gas tank fairly low and having a fire extinguisher nearby just to be safe. Lots of gas fumes and the pump is obviously covered in gas when it comes out. I had no problem doing it safely myself but be careful and take your time.
I do recommend running the gas tank fairly low and having a fire extinguisher nearby just to be safe. Lots of gas fumes and the pump is obviously covered in gas when it comes out. I had no problem doing it safely myself but be careful and take your time.
