I'm guessing this is a 240? (Posting MODEL & YEAR gets more focussed responses, IMO.) But some of your symptom descriptions don't fit what I understand about Volvo FI and ignition systems in general...

Does anyone else know of something that shuts off the ignition the same way a bad pump relay does?
That's not how it works. Lack of Ignition prevents the Fuel relay from energizing. Been that way for years.

So I can't imagine how you can "...have no voltage on the coil...and the pumps are running.."

Also — "I checked the pump relay with the cover off, and it seemed to be switching well"

The Fuel Relay (one of two relays under that cover) should never "switch" except for a brief run with Key ON , until spark is detected during cranking and running). However, the "System Relay" does come on and stay on with Key ON, but doesn't power the pumps.

Bottom Line — Verify Ignition(or lack thereof) FIRST, before chasing FI problems that may not exist. (BTW, Fuse 6 replaces the older 25amp underhood fuse.)


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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.