I think he said his is a 5.6L ... wouldnt that probably have a different setup than the 3.0L ?

A fuel pressure regulator works the same in all models It's part of the CIS system we share.

no, you shouldn't smell any gasoline at all under the hood....never...in fact the only time you should smell gasoline is at the the station.....

I'm having the same issue. 1987 300E M103 engine, started to develop a gas odor at idle or when parked in the garage after arriving home. Sometimes, quite pungent. So on a cold engine, I removed the air filter, exposed and wiped down the EHA, and started it up....sure enough, it's weaping from the body of the EHA and not from the seals. ****. So I ordered a new EHA...
But here's my question: is it a bolt on job? I've read that some EHA's need calibration? Would it come calibrated or is it engine specific and I would need to do that? (not sure how to, nor would I have the tools)
Thanks guys.
Cam

__________________
1987 300e W124 M103 My baby.

As Ferdman said, a fuel odor under the hood is likely the EHA. At least, that would be my first place to look. It's simple really, remove the air filter (three bolts, detach two hoses, and voila!), and expose the distributor. The EHA valve body is a little black unit attached to the distributor toward the back of the engine compartment. First, on a cold engine, get a clean rag, some degreaser, and clean the unit thoroughly. Now start it up (yes, it will run without the air filter on). Using good lighting and a mirror, inspect the EHA all the way around. If the EHA starts looking wet, there's your odor. If this turns out to be your problem, the next step is to investigate if it's the EHA ($350) or simply bad gaskets ($3)...
Good luck!

__________________
1987 300e W124 M103 My baby.

I had that smell too. It turned out to be a cracked vacuum line and connector. Fixed it for $7 .

__________________
1990 Mercedes 300 SEL (320,000 miles)
1994 Mercedes E420 (140,000 miles)

Which vacuum line?

__________________
1987 300e W124 M103 My baby.

The fuel pressure regulator vacuum line?

__________________
1987 300e W124 M103 My baby.

This is not a vacuum line. It is an escape tube for the fuel to the AFM if the diaphragm in the regulator goes bad.

If you see fuel in this tube, your regulator is on the way out. (the car wont idle or drive properly either).

Another source for small fuel leaks is the fuel input on the side of the fuel distributor. There is a filter there with a crush washer. Make sure this is tight. Better still change the filter - it's only a few bucks. You will get a new crush washer with it.

On a 300e W124 there is a return filter under the drivers side guard. These are supposed to be changed with a certain time or distance interval. They rarely are ever changed. You need to remove the plastic cover in the wheel well to get at it. Sometimes they blockup and cause a fuel smell.

One reason I keep my engine bays very clean. You can see leaks and other problems easier. Petrol leaks -look for the give away colour of the die from the petrol. On a clean engine it's very easy to spot the colour.

I talked to the Mercedes tech today that used to service my old 380. He explained to me how to easily check it (EHA) for leaks and said there was no danger. Also like I found out here, he said it was a common problem on older MBs and its either the o-rings or something else inside the EHA - (forgot what he said). He said if not, I could bring it in and he would check it. As soon as this dang rain stops I will check it. If its leaking, I will take it in for repairs. Thanks again!

I just wanted to update on this... some of you may remember that I said my 300 had a fuel smell under the hood (could smell if you put your nose down to the fender/hood crack and that I thought it was my EHA valve. I called a local MB tech (as mentioned above) and he said it was probably the EHA and I could check it by removing the air filter and feeling behind the distributor. He said there was really no danger on that particular engine, since the manifolds were on the other side of the engine.

Thing is, two days later (almost three months ago) the gas smell completely went away and I have not smelled it since! Is it possible for a EHA to leak for awhile, then stop for months, then leak again, or? Strange the smell went away and has not returned. Should I still have the valve replaced?

Thanks.

I just wanted to update on this... some of you may remember that I said my 300 had a fuel smell under the hood (could smell if you put your nose down to the fender/hood crack and that I thought it was my EHA valve. I called a local MB tech (as mentioned above) and he said it was probably the EHA and I could check it by removing the air filter and feeling behind the distributor. He said there was really no danger on that particular engine, since the manifolds were on the other side of the engine.

Thing is, two days later (almost five months ago now) the gas smell completely went away and I have not smelled it since! Is it possible for a EHA to leak for awhile, then stop for months, then leak again, or? Strange the smell went away and has not returned. Should I still have the valve replaced?

Thanks.