car was running fine, had a stumble like it lost power wanted to die and then was fine, did this a couple of times for a few days and then it died while driving and will not start anymore. fuel pump relay is good (it will start the other volvo) it has spark and the tach bounces while cranking. i was following no start checks for the LH 2.2 and found no injector signal while cranking, .2 volts insted of 12 for power to injectors, .2 insted of 12 for the O2 sensor preheater, and 12 volts at the AMM like it is supposed to have. now im not sure what to look at next other than a bad ECU maybe.

The good +12 to AMM comes from the Main/System relay, which lives in same white case as Fuel relay, but picks when key turns to II/On position.

Those low voltages come off Fuel relay 87/2, the same point that powers the pumps.

If that relay works in another car, take a close look at the harness plug terminal for 87/2 (Y/R wire).

Or...(hate to say it) the ECU may not be grounding Fuel relay 86-2 Blue/Green coil ground side.

And--- alps's tip (below) on the 25 amp fuse is good too. Look real close at the fuse wiring. Amm +12 comes from that fuse, but it may not pass enough for everybody.

Quick check: Jumper between fuses 4 and 6 (left side contacts) and try starting. This bypasses the 25 amp fuse and fuel relay. Should start, if spark is good.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

well its not the 25 amp fuse, that is fine and the conector alltough a little corroded is not an open circuit. the wiring on the conector of the fuel pump relay is in really good condition, how do i bypass this relay to rule out other things? it is the white one with the four conections, right next the the fuse panel right?

well its not the 25 amp fuse, that is fine and the conector alltough a little corroded is not an open circuit.
• The wire corrosion is usually worse at the battery end of the fuse wiring. It can be "not an open circuit", but lack current-carrying capacity for all FI loads.
Might be worth another look.

the wiring on the conector of the fuel pump relay(?) is in really good condition, how do i bypass this relay to rule out other things? it is the white one with the four conections, right next the the fuse panel right?
• NO — the Fuel relay is above the passenger's feet, on the inside of the firewall. Remove the black "hush panel" for access. It is white, but has six terminals. There are actually two relay inside: Main and Fuel. Main should click with Key ON -- Fuel relay not until cranking/running.
Off hand, I don't know what 4-terminal relay you found by the fuses.

"..how do i bypass this relay to rule out other things?"
• Try the "Quick Check" that I suggested in my first post, above.
The pumps should run immediately, so try starting.
It should start if ignition is OK, and the FI Main relay clicks when the key is turned to ON (pos. II). Be sure to test for that when you've found the correct relay.



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

ok by jumpering the fuses it starts, i found the fuel pump relay and opened it up. it looks like one of the solder joints one its is bad, so i will resolder and see if that works.

Just had this problem last weekend.
Jumped the fuses and still had intermittent starts.
Cleaned the battery terminals and replaced the 25 amp fuse. Eureka.

Try checking that fuse on the wheel well between the battery and the coil (25 or 30 amps) enclosed in a white case. Maybe it's not making a good connection.
Al P.