Hi,
My 1986 740 nonturbo sedan has been running smooth since last June. On rainy Friday, I pull into the driveway and was idling while I waited for my wife to come out of the house. The engine dies without warning. It won't restart.

I checked to make sure that my distributor low voltage cable is still plugged in. (It fell out one time after I had replaced the distributor last June).

I check the spark by pulling #1 cable off of the plug and put in a spare plug that I ground to the exhaust header. Looked like a good spark.

Next day I changed the distributor cap and rotor thinking it may have gotten wet from the rainy Friday. I put in new Bosch plugs. Still won't fire up or even sound like it wants to.

I switch out the CPU - no change

I have fuel at the rail since I can see flow at the discharge of the pressure regulator when I hot wire the main fuel pump.

I spray ether into the intake manifold through a hole where a large vacuum hose was connected. It makes an encouraging sound like it wants to catch for the first time since friday.
I suspect that the fuel injectors are not getting a pulse. I see an injector relay in the Volvo wiring diagram. I also see wire rot on the water temp thermistor. Please help. Thanks