bora

I filled the car up the third time since I purchased it, and it has done this every single time. I fill up until the pump clicks, then close the gas cap, and
go home put the car in the garage.

Then the whole garage smells of gas.

I am thinking maybe the gas cap is leaking and causing gas fumes to escape, or I have a gas leak. The fuel mileage is in 19-20 mpg which sounds bad for a 240 but not that bad. So I am leaning towards a bad gas cap. I have never had a bad gas cap in any of my other cars before and I did not want to have one in this car.

So far owned the car for 1.5 months and have been at the dealer three times. Sure love that Starmark certified experience.

bora

Mystery solved, there is gas leaking from either the fuel filler neck or where it attaches to the gas tank. Got under the car and started looking towards the tank from the right rear wheel, and the wet trail of gasoline is hard to miss. Back for service tomorrow I guess. The only question that I have is how the hell did these guys miss the leaking gas stains when they installed the sway bars. Since one of the spots is right next to the rear sway bar mounts.

Buellwinkle

Boy, at what you guys pay for gas up there you want to account for every drop. Has premium hit $2.50 yet? The cheapest of the cheap stations by me are at a little over $2.

bora

I think I got the last tank of which 1/8th of the tank leaked overnight at 2.11 a gallon.

I dropped the car off today and basically told them I don't want it back until they fix it.

I have three other cars, so I am not in a hurry to get it back.

MarkL

That's interesting -- I'm wondering why you didn't get the check engine light coming on. They always say if the cap is loose, the OBD II (whatever) will detect it. Is a leak further down similar in that a seal to the atmosphere is broken?

bora

I am asking myself the very same question, I wonder if it detects loss of vacuum or it detects broken electrical contact or resistance change on the gas cap and the fuel filler neck.

bora

Dealer just called, gas tank is cracked where it attaches to the fuel filler neck, it is not the neck itself. They need to get a new tank from either germany or east coast. Estimated down time 3-4 days.

I don't know what's involved in getting a new tank installed, but any recommendations on what else I should have them look at while they are in there.

Matt230K

I had a new tank put in my coupe for a different problem. I'm not sure if it's in the same place in the sedan, but they had to unbolt the right side of the rear subframe. If they have to do that, make sure they do an alignment.

If the tank is really the problem, then there shouldn't be anything else to worry about while they're in there.

Jens C320

Depending how bad the crack in the tank is, I would get them to change the fuel filter (not sure where it is located on the C-Class) just to make sure it isn't getting clogged because of contamination.

Outland

Certainly something like that should have been noticed by the previous owner...at least an owner with a nose

Matt230K

Well, it probably just happened, but if not, then that may be one of the reasons that they got rid of it.

bora

It did not **JUST** happen, we noticed the terrible gas smell after we signed the paperwork and drove the car home from the dealer with a full tank of gas. It used up an 1/8th of tank of gas over 10 miles. I just chalked it up at that time over to the dealer over-filling it.

I like the car, never had a problem like this with either my Porsches or BMWs.

Oh well, as long as it is fixed, I am happy. In the meantime I will ask them about the alignment.

Matt230K

Sorry, I had to reread above where you said it happened with every fill-up since you got it.

bora

No problem, I am glad that the service department found it (finally) and fixed it. It puzzles me as to how an owner would miss filling up the tank and then coming back to it in the morning and finding 1/8th of the gas gone.
This is if you could not smell the gas in the garage, my whole house was smelling like gas after a while.

trench

Frankly I'm often amazed at people's powers of un-observation.

My guess (since this is the Bay Area) is that the previous owners may not have had a garage and therefore never noticed any smell.

- BT

bora

Quite possible, the car actually came from Missouri, but the owner may have had other toys
to park in the garage.

bora

Dealer called, new gas tank has arrived, it is going to take them 2 more days to put it in, apparently driveshaft and differential needs to come out as well as the sway bars but not the trailing arms etc.

Well I sure hope they don't break anything else in the process.

39039

I fixed it.