"Not sure how to do the jumper wire test between #4 and #6 fuses. Should this be done with the key in ACC position?Not sure how to do the jumper wire test between #4 and #6 fuses. Should this be done with the key in ACC position?"

The objective is to get +12v from fuse 6 (fuses 6 - 10 always have battery voltage, but 6 isn't really used on your car) and apply it to fuse 4. Use any metal object to connect those 2 points (expect a little sparking as the connection is made). I recommend connecting the LEFT (input side) for both fuses.

The +12V at fuse 4 input goes in 2 directions:
• Thru fuse 4 to the Tank pump, and
• Directly to the Main pump

This jumpering can be done with the key off. Both pumps should run immediately. Using a jumper wire with alligator clips will let you go to the gas filler pipe to hear if the Tank pump runs. The Main pump is under the floor pan on left side.

If you hear both pumps run, keep the jumper in place and try starting. If the engine fires up, the jumper has bypassed the 25Amp fuse and The Fuel relay, either of which could be faulty.

If it doesn't fire, check for an ignition problem. Remove a sparkplug and reconnect the high tension lead, place the plug where it's metal body is in contact with a metal ground, and look for a spark when cranking.

On the '87 the coil primary wires are routed thru a 2-pin connection which can get corroded and cause a spark failure. See below...



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