If the EHA is leaking from anywhere but the o-rings, it's shot, you'll want to get a new one or source a good used one (I would just try ones from junkyards, I wouldn't pay much money for one). I'd bet it's at least part of your issue. Other thing I would recommend is pulling the OVP relay and reflowing all the solder joints.

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.