1991 Volvo 240 Intermitant fuel pump problems

[yosef7]

Thank you. I think this note will go to thread correctly. I am still learning how to reply.

You suggested: Once you find the trigger wire you can always run a tap to it and have a wire you can touch to positive to make the pumps go (by activating relay with 12v power source)

I am thinking of putting a toggle switch between the yellow/ red wire on the relay and a 12 volt power source. Will that work? and what would you suggest as the 12 volt power source? The battery? another fuse ....?

How difficult will it be to change out the ingnition switch?

yosef

[yosef7]

Sorry. I just found the info you sent me with the relay testing. It is extreamly helpful. I will test first. I know that when the pump does not hum I don't have power to 87-2. When it hums I have the test light , lit. So if I pull the relay and put a heavy wire between 87-2 and 30 I should hear hum.
Can I drive in this mode? How heavy a gauge wire would you suggest? I will try all of this later this afternoon, and let you know what I accomplish -yosef

[JDS60R]

The relay activates several components so I would fix the situation rather than the jumper. But in an emergency yes you can run power direct to the pumps. I would want at least the same gauge if not better than the wire connected to it now. Leaving the power connected when the car is not running may damage the pumps or cause an overheat or fire condition. ( This is why there is a relay in the system by design)

[yosef7]

Just tried to start again. No hum. (no start) Took relay off. Checked for power. Power at red (30) slot. Tried to jump wire from red (30) to Y/r (87/2) and got nothing. No hum. Any ideas. 30 was hot. I am going to check all the grounds again. Back after lunch.

[JDS60R]

This is good information.
You now know either the wires to the pumps, the grounds for the pumps or the pumps themselves are bad.

Run power from 30 to 87/2 again and test for voltage at the plugs for the pumps. Lets see if its a bad wire or a bad pump/pumps .

lets us know - Now we are getting somewhere !!!

[JDS60R]

Question

Was 87/2 hot (12v) when the relay was on?

[yosef7]

First off, thank you for everything you sent. If I did not have the suggestions you sent I would have more dents in my head. Relays were all good. Grounds all good. So I had to just follow the yellow/red wire back to the ingnition switch. Behold, I found a bad spot in the wire. Cut, spliced and all is good. Hums better than before. So I am grateful for all that you sent me. I am grateful for this site as well!!! Thanks!!!!!
yosef

[iaguilera]

good day all, I am new here, my son really wanted a 91 Volvo 240, or just a 240 period, he found a 91, I have replaced both pumps and the pumps relay, the high pressure pump is not humming, it only does if I connect a ground to 86/2 pin on the relay, then I hear the pump running, any ideas how to go about fixing this?