ultraseven

Before anyone replies with STFF, I've done exactly that and found this to be a fairly common problem with C classes here.

For me specifically, I have an 04 C32 and it has been in the shop several times for an erratic fuel gauge. The dealer said they've replaced the cluster, the SAM, and updated the software but none of those addressed the problem.

Has anyone had a similar headache and what was your fix?

SilverBulletAMG

Mine JUST started doing that! The last 2 times I filled up it reads as 3/4 full or just a tad over. I had searched for an answer to see if this was common and didn't find anything either. I was hoping it would correct itself in time. I was going to run it all the way to fumes and then fill up and see what it does. If it's still acting weird, off to the shop....again.
I'm actually kind of glad to see someone else is having the same issue. If I end up having to take it to the shop over this, I'll pass on anything they do. However the answer is always to troubleshoot with new parts and repeated trips back for the same issue(s).

jturkel

i had this problem. if i remember correctly, the dealership replaced the "bob" or some part of it that detects how much is in the tank. a faulty bob or w/e part may cause faulty readings.

Tump43

Fuel lever sender problems seem to be common to all MB's after about 40 to 60k miles. I had the dealer replace both of the integrated fuel pumps, fuel level senders and fuel filters contained in my C55 gas tank under the OE warranty before it expired.
This was also a problem on my 99 C43 and 87 300E. However, on each of those cars it was easy to replace the fuel level sender myself, not so on the C55 (the gas tank has to be dropped).

SilverBulletAMG

I just hit 49k so I guess mine is right on cue. I will pass the info on to the dealer. Thanks for the heads up.

Popo

I had the same problem in my 2002 C32, and a buddy told me that it may be gunk buildup on the fuel sender. I did 2 things to fix it. 1) put a bottle of fuel system cleaner in the next tank, and 2) switched to a different fuel manufacturer for the next 5 tanks. This has worked for me so far.

Hope it helps someone.

60n5pt1

My needle starts going down slow at just below the quarter mark (3/8?) and stays there with about 2-3 gallons left. Eventually, the 'visit refuelling station' prompts lit up.
One time coming in at a fastfood drive thru the gage read less than 1/4, after five minutes waiting for my order, the 'visit prompt lit up. I ran out of gas 1/8" of a mile later.
Also, even after you fill up, the needle stays between 1/4 - 1/2 initially and after a couple hours of driving, slowly shoots up to almost full tank.
Any cheap and quick fix for this?

SilverBulletAMG

Worth a shot. I've never ran any fuel cleaner through the car since I've owned it. Any particular brand to shoot for or stay away from?

60n5pt1

As for gas brands, I've always filled up at Chevron (Bay Area) or Shell.
Don't know any after market fuel cleaner additives since, I believe, MB doesn't recommend.

but check out this site:
http://solutions.3m.com/wps/portal/3...l_Sys_Cleaner/

Popo

I used the techron stuff, and switched to Shell V power from Costco fuel.

ultraseven

The aftermarket additives are all gimmicks. All of them are inert chemical compounds which doesn't do anything except adding to the exhaust fume.

As for the latest, my SA told me MB Engineering needs to send them a software update for my car. Has anyone had something like this before?

SilverBulletAMG

I'm not sure if it is pure coincidence or if the fuel cleaner actually worked, but either way, I picked up some fuel cleaner this morning and added it to the tank when I topped it off. Within 10 minutes my fuel gauge corrected itself! Every time I started the car today it read correctly for the first time in a couple weeks. Go figure....

OJwerks

mine did it after the car had an empty tank for like 4 months... since it had been sitting around for a long time... after a couple fill ups it fixed itself...