W126 Visible fuel leak on intake manifold!
 

'87 W126 (560 SEL) 164K I have done a search, nothing like this I have read yet. I have a visible fuel leak on my intake manifold behind the air filter housing. After going out for breakfast I thought it was the car in front of me until I arrived home. VERY strong odor of gas. With a flashlight I can see where fuel is 'pooling' up in a crevice of the intake manifold. There also might be a leak by the distributor, the sensor that stands vertically right behind the distributor, not sure if that is a cold start sensor?, but a smell of gas is too close to the distributor in my opinion. I don't want my baby to catch fire! The tank is only half full and no there is no smell of fuel coming from the rear near the fuel pump (back one) It was about 58 degrees this morning, cold start have something to do with it? I have started it after the fumes dissipated and it seems to be running normal with no smell of fuel in the engine compartment. Now that it is warmed up it does not leak?

:confused:

Have you looked for the leak with the engine running? I had the raw gas smell too, finally "caught" the leak in action. In my case it was the cold start valve intermittently leaking where the injector mounts to the flange/body. The years had taken their toll, and the injector was slightly loose in the body, which allowed it to move a minute amount. When it moved it leaked.

Your leak could be coming from any of the fuel lines or fittings. The cold start valve is only active when the engine temp is below 35dC, and only operates for a few seconds during start-up, but there is constant pressure on the valve even when not operational.

I would check the EHA which is located in that vicinity. it is on the side of the fuel distributor (drivers side) and looks like a small black box they tend to get old and crack ever so slightly and they have two very small o-rings thart seal it. Clean it and watch it while the car runs.

I am writing two messages so I could get the first one in before this storm knocks me off. I am in Birmingham AL and it just hit so.... those eha's leak all the time and they are around $150 to 200 and are easy to change. Watch your eyes when you first unscrew it because it is under pressure and somehow knows exacly where your eyes are. Good Luck.

The next morning...
 

Well it has been confirmed. After a second cold morning the verdict is in. That little black box on the driver's side of the fuel distributor is DRIPPING with gas. After seeing it, I took off the air filter housing to find it drooling gasoline all over my intake manifold. So now I know what is my problem, but what is a EHA? Looking at my performanceproducts catalog, the part seems to be the 'Fuel distributor govenor 5.6' part # 07-042 for $15X.XX (catalog 126-7 Spring/Summer 2001). Is this the same part that might be the 'EHA' ? What I am also worried about is that this part looks I might have to remove two of the fuel lines coming from the fuel distributor to remove the governor, I am hoping that is not so. No smell of fuel by the cold start valve but there is gunk buildup by it, will acquire attention as well. EHA=Fuel distributor govenor 5.6?


Hoping not to make a dealer trip,

SqueakyBrake

The EHA (electro hydraulic acutator) is a pressure regulating device that adjusts the air / fuel mixture. It is driven by the Lambda computer. It is simple to change. Remove the two screws holding it on and replace the two small O rings that seal it or replace the entire unit. You should not have to disconnect any fuel lines to change it. Be aware that fuel may squirt when you loosten the screws.

I highly suggest replacing the whole unit as they usually have a hairline crack in them that you can't see. They replace the choke on a carb car or the waem up regulator on the older v-8's that mercedes have. Just take a screw driver and stick it between the fuel lines and it should come right off. Be sure to unplug it first. I always use the scews that were originally on it because the replacements are torx and a pain. I am not a fan of torx heads and therefore another reason not to like the M-cass garbage that they make down the street.

Right here, through MercedesShop, you can get a new EHA Valve from FastLane for $150.73. Their shipping has been lightning quick on every order I've placed.

Success!
 

I chose to buy the part from the dealer (came with the o-rings)>$240. It seems I was having tomato, tomatoe part name callings. The EHA is the 'Fuel distributor governor' and many more names to go along with it. As all has posted it is a very easy removal/install but I do suggest wrapping it in a paper/shop towel before removal, fuel did soak mine within seconds, eye cover without, thanks for the website! My first DIY :cool:



SqueakyBrake

Good job!

You'll find yourself looking at more ambitious projects before too long ;).