560SL strong gas oder inside of car
 

Gentelmen

Occasionally I get a gas oder in the interior of my 1988 560SL. The gas oder is not under the hood or underneath the car, just inside. And so far it has only happened about 5 times in the last year. Yesterday was the worst time it ever happened. I had what I belive was dirty fuel injectors so I put some Techron in the tank and drove it hard to try and clean them out. The tank was full. I stoped, opened the hood, removed the air cleaner and ran the car for a while in my garage. When I opend the door to get back in I got a very strong blast of fuel oder. I checked all the fuel injection lines for leaks and the fuel pump. No smell of gas in these areas. The problem subsided after a short drive with the windows opened but I do expect it to happen again in the near futer. Any ideas are greatly appriciated before I pull the gas tank.

John Roncallo

Not sure.......I've had this problem before..some say it could be your fuel cap that is leaking..also could be an oxygen sensor going. I think this was what fixed my car.

not sure
 

on an sl what the configuration is but on the sedans there is a drain from the inside of the gas filler cap that drains thru the trunk area with a rubber hose. if the hose fails you get fuel in the trunk. could be something similar in an sl.

tom w

I had the same problem with my '87 560SL.

It is apparently quite common (as someone already mentioned) for the fuel caps to go bad. Definately change this first (only use an original MB cap.. not aftermarket!)

This made a big difference in my car. However, the fuel smell never totally went away. Not sure if I was smelling residue of fuel in the car or something (I only owned the car for 6 mos after changing the fuel cap). But there was definately a big change in swapping out the fuel cap.

Neal

Check you EHA
 

Even though you say it's not in the engine compartment. It's located on the drivers side of the air intake under the hood. The o rings go bad and it leaks gas. Very common. You should see nothing wet on it. O rings are replaceable.

JB

I just found a completely broken hose from the charcole canister. It's under the left front fender. I will try replacing that first, but I still dont know how the oder can pass from that point to the interior.

J. Roncallo

I had similar problem after using same fuel injector cleaner. It was a gaget just prior to rhe fuel injection syatem. Possibly the O ring mentioned in previous post. Happened years ago and I do not remember details.

That would be nice If its that. I will check it out.

Thank You
John Roncallo

is there a gas odor in the trunk? there is a vapor canister near the tank that may be causing fuel odor

I never had a gas oder in the trunk.

JR

The part with the o-rings is called an EHA electro hydraulic actuator, the orings do leak at times.(next to fuel distributor under air cleaner cover).If replaced, lamda needs reset/adjusted.
If it were my car, I would pull the fuel pump package cover off and take a real good look at the rubber fuel hoses and banjo fittings going to and from the fuel pump, sometimes you can't see what's lurking under that cover.
Should be 3, 10mm plastic nuts holding the cover on.
Good luck.

I actually did this yesterday. I have found all the rubber hoses to be old but no sign of leaks. I am replacing all hoses in the raar as well as a broken hose (completely severed) at the charcoal canister. I think the caniser hose is the problem. Some way the oder maybe getting from under the front left fender to inside the car. No sign of leaks at the EHA. Of course this problem only happens about once every 2 months or so. So it will take about a year to know if I really got it.

J. Roncallo

Thanks to all who replyed

It does apear at least for the moment, that the problem was the fuel cap. The past week, I was smelling the gas every day. With the new cap so far all is OK.

John Roncallo

I need to update that. I never had gas oder in the trunk until last week. Since then I'v had it very strong every day until changing the fuel cap. I hope this fuel cap was also my original periodic problem I was having and not just something new.

John Roncallo

Unfortunatly the gas oder still presists. It is significantly better with the new gas cap but not all gone. I would like to check the expansion tank next but I dont know what to look for. Is there anything inside these tanks or are they just empty cans with 5 hoses going to them.

John Roncallo