OVP almost certainly for your problem. Check the fuse first before replacing it. It resides behind the battery and is red. It will have a fuse/two fuses on top. With any type of stumbling/stalling/light problems....OVP should be the #1 thing to check on the M103's.

EHA cannot be tested for working condition....In my 260E, it would bog down at low speeds then suddenly pick up. Fuel pressure on the lower chamber was dead on spec....I swapped the EHA and it was a completely different car. The EHA would not cause stumbling or stalling...only a loss of power at the bottom end.

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