EHA Leak; rough cold start
 

I noticed that there is gasoline seepage at the joint b'tween the EHA and
fuel distributor in my 1989 300E. I replaced the 2-green seals, cleaning
the seats first. I also notice a rough (sometimes a fiailed start, like running
for 3-4 seconds then stopping) at a cold start.

1. Are the two problems linked?
2. How can I test the EHA? I've followed the EHA threads in the Forum,
but am a bit confused.
3. Is there a bench test for the EHA? Like putting a voltage
on it to see if the valve opens/closes? Is it open or closed
with no voltage?
4. It is a bit expensive to just try a new EHA unit. Replacing the
seals did slow the seepage, so can I cut a full gasket w/ the proper
passages to fit on the distributor, and stop the seepage?
Or if it is seeping, does that imply that EHA is not functioning?

Thanks in advance for any help!
B.

If you put on the new seal rings and know they are seated properly and it still leaks then you have a bad EHA! No real way to fix them that I have seen. As for testing one! The only thing you can do is follow the test procedures of checking the amperage drawn as specific RPM's from what I have seen! And no I do not know the procedure. Just that one exists.

EHA replaced; much better !
 

I found a new Bosch OEM EHA (1/2 price of MB list!) The old/original one
was holding pressure at the green seals, but seeping gasoline thru holes in
the plastic body (maybe a teaspoon/10 miles?)

Replaced it and the old 103 engine works much smoother, plus no gasoline
smell (leak.) Now maybe I'll pass the state emissions test next week!

When I replaced my EHA on my 420 it took a couple of adjustments to get it to run correct. Then the duty cycle had to be reset. About 1 1/2 hours of playing with it and now she runs like silk, and no gas smell. Also my milage improved to 22.6 on the highway. Not bad for 80mph and a very big car.