Can’t fill the gas tank - 1996 Mercedes-Benz C-Class

I can’t seem to get gas into my tank which registers full after a few gallons then runs out of gas when the gauge is showing the tank is 75% full. I have been stranded so many times I’ve begun to just leave the car in the garage. The car runs smoothly when it runs and the interior/exterior are in pristine condition. I really would like to hang onto this car I’ve had for 20 years+ with low mileage. (App. 50,000 miles). Local mechanic says he doesn’t know whether it can be fixed or exactly where he can find parts. Any advice?

Your fuel pump pickup has broken or fallen off so it can’t reach the bottom of the tank. Not rocket science to fix. You mechanic just doesn’t WANT to fix it. Find another.

Thanks for responding. I’ll definitely have it checked out.

as a matter of fact . . . this car has TWO fuel sending units, because it has a saddle tank

Quite expensive to replace, as there are very few aftermarket fuel sending units available

As far as not being able to fill up . . . that may very well be a separate problem. The likely problem is part of the evaporative emissions system, and it’s a sort of expansion tank, NOT the canister

How much money are you willing to spend to resolve these problems . . . several hundred?

I’m asking, because the proper fix is going to cost you a lot

In the meantime, you can start filling up with top tier fuel . . . it may clean up some of the deposits on the fuel sending unit contacts

I agree with @Mustangman . . . either your local mechanic doesn’t actually want to bother diagnosing and/or fixing the car, or he’s lousy at finding parts.

Does your mechanic use a professional information website to diagnose this car . . . or is he just thinking it must be the same as a Chevy or Ford, for example? There are some differences, and if he’s just guessing, it may lead him down the wrong path . . . tell your mechanic to look at that parts website

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Thanks so much for the advice. I know the car is more valuable to me than its market value so I would be willing to spend several hundred to get it back on the road. Of course, if several expensive repairs are In my immediate future I’ll have to let it go. I’d hoped to keep it as a summer car for many more years.

Considering you don’t want to invest a lot of money . . . start filling up with top tier fuel the very next time you get gas. Costco fuel is top tier, in case you’re a member

It may make the fuel gauge function reliable enough, that you can live with it