Hi just-n-time here, I have had a gas odor in the trunk, I have spent a good deal of time under the car trying to find wet lines but no luck,today I replaced the fuel cap and my wife said as soon as I did that the smell stopped, So I thought maybe it is the o-ring under the fuel sending unit, I replaced it too. I found no obvious damage to the o-ring.Has any one else had this kind of trouble?1990 420sel

I had the same problem with my 420 SEL, 1990- for me it was the fuel cap....

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"It's normal for these things to empty your wallet and break your heart in the process."
2012 SLK 350
1987 420 SEL

Try replacing the rubber flange that wraps around the filler neck.

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1989 300E 144K

Found the leak,When I replaced the intank filter the hose from the tank to pumps must have bean at the replacement interval,for it is now bleeding. well Phil has one on the way. Thanks for responses JNT.

yes i have that odor aswell, havnt done anything about it yet just have been woried, i examed that there are no leaks, and the cap seems to be locked in, everytime i open it i am happy cuz it makes a air seeled swish. lol but i would love to know what you did to stop the smell,

Replaced the fuel cap it was over pressurizing the system and the main fuel supply line to the fuel pumps was week and the extra fuel pressure came threw the line.(threw the walls)

yes i have a simmalar problem and i couldnt figure out what was wrong either, i replaced the cap and the smell stopped, mine was so bad that the smell went into the cockpit, i have an 87 420sel

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I can do 111mph with no gas, no oil, and no power staring, threw traffic. Can anyone else do this one a 20 year old car? I think not.

I used to have a g35, now I took this Benz and made it quicker, more agile, and much roomier then the g, **** Japan rock the German engineering.

I once had an olds that needed to have the carbon blown out,so the Long island expressway seamed to be a good place at 2 AM,the officer did not think so nor did the judge,even more so when he asked why I was traveling 98mph on the L.I.E. I told him quite frankley the car would not go any faster!

One of my 124s developed a leaky fuel hose near the fuel pumps. The smell would drive you nuts!

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2012 E350
2006 Callaway SC560