Ethanol ate my EHA?
 

Background, i have a '91 W124 300E that used to see regular driving but then became a backup car that sat most of the time. It got harder and harder to start when cold each time until it eventually just wouldnt start at all. If you poured a little gas down its throat it would start and run for a few seconds and die. Over a period of a year or so, I went through all of the checks that are recommended on the forums for this problem and replaced several parts with no joy. I eventually replaced the EHA simply because I'd gotten one of a 300e at the salvage along with several other parts and THAT is what fixed it. The old one looked fine and had been replaced about 4 years prior.
The strange thing is, the very next morning, the car wouldn't start again. I replaced the EHA again with another one I had from the salvage and it started and ran fine once again.
I had been running ethanol fuel in the vehicle this whole time and it had gotten a bit stale. There were no signs of dirt or contamination in the EHA or the main filter. Is it possible for ethanol fuel to take out an EHA?

It would not surprise me, especially if it sits up a good bit. Maybe thy Stabil for ethanol treatment?

YES
 

It can damage the system.
http://www.peachparts.com/shopforum/vintage-mercedes/330271-ethanol-can-wreck-your-classic-car-fuel-system.html


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