Hi guys, I'm new to the forum, so would just like to start by saying thank you for the great resource on these cars!

Here's my issue:

1992 Mercedes 300E 3.0 2wd 145k. Car broke down this morning. Dim lights, dim dashboard, very slow wiper, dash warning lights abs/srs/bulbs came on then the car cut out. Tried to crank it...nothing. No electrical power. Two minutes later it cranked and started right up. A minute later same problem occurred. Two minutes later, started right up. Repeat this all day. Now, once the tow truck got me home, I looked into it as much as google would let me (a lot), and everything pointed towards a bad alternator and/or a bad Voltage Regulator. So I changed the alternator for a new one. Started right up and ran perfect, idled for a good ten minutes no problems. Went to reverse it out of my garage, on came the warning lights and she cut out again. Now I am stumped. There's a relay that protects the system from voltage overload - I checked that and its own fuse which was good. Battery leads are all as new, battery is good, what the heck is wrong with my car?

I need help so badly, this is my daily and I had to take an unpaid day off today for the alternator which didn't cure the issue. Also, I searched as much as I could on this subject but couldn't find much, so apologies if the search engine didn't do its job.

Thanks guys I hope someone has some words of wisdom. Cheers!