I would second this. Replace it if you have a spare, or better yet try your AMM in a similar year car (85-88 240 or 740).

I had an 87 that had some high-load stalling issues and it turned out to be bad connections at the AMM.

A second problem which that car had really stumped me till I was able to reproduce it in the shop: it would stall at random and sometimes immediately restart, sometimes not.

There is a connection under or behind the coil, a two-pin plug with the red/white wire and I think a blue wire in it. Grey plastic plug. The plug on ours looked seated but was definitely not. Unplugging it and re-seating it solved everything. The way to prove that this is the case, use your voltmeter to check for 12 V at the coil terminals. Should be there at both terminals when key is ON but not running. If it's absent, try moving this connector. In ours I got an immediate BZZZZT from the fuel pump once it made connection.

Took me three hours of idling on the lift in the shop to catch that one.

Good luck with yours!
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Rob Bareiss, New London CT ::: 87 244DL, 88 245DL, 90 745GL, 84 242DL project, 89 244 parts, 88 244DL to replace the 87