I'm looking for help identifying the alum. box under the hood of my 85 SL380. The name on the box is "ProgRama" Made in U.S.A.. Replaces MB0025452632/Bosch 0227100042.

I suffer from a rough idle (pro stock rattle) but it holds great at 600 RPM. At speed it seems to pulse when driving. I am wondering if this should be replaced with factory.....not even sure it could be part of my problem.