No power to fuel pump, seems to be a common problem around here Options

[warrenoliver]

Car stalled on me this morning. When I tried to restart, the fuel pump would not turn on so no luck with the start. Towed it home and checked it out. It is a 73 2.0 with FI.

The pump runs when I jumper directly to the battery. I have continuity from pump connector to the #13 pin on the relay board. If I jumper from the fuse to the #13 pin, the pump comes on. The fuse is good.

I have replaced the main power relay and the fuel pump relay with known good ones. With the ignition on, when I remove and reseat the main power relay, I can feel the relay click but I do not hear the injectors click nor do I hear the fuel pump start (I got this test from Dr. 914's Tech Tips).

On the fuel pump relay socket, I have power at the 30 pin and also the 85 pin. When I jumper to the 87, it does not turn on the fuel pump.

I don't know if it is related, but I have the same problem with the heater blower relay also. I jumpered 30 to 87 and I do not have power. I am not sure but I think the car died when I had the heater blower running.

I'm stumped. What do I check next?

[Tom]

Warren,
I agree, you are getting very close to the problem here. Actually read the whole post first and try cleaning up the fuseholder to trace rivet area. Sometimes just cleaning and moving this area can regain good contact.
Here is the next test I would do to confirm that pin #30 of the fuel pump relay socket has a connectivity issue. Remove the relay itself and wrap a small wire around the #30 pin, reinsert the relay back into the socket with the small wire sticking out, ( a small paper clip could be used also or some small solid conductor wire), now try the key on - pump should run for 1.5 sec. It didn't before and expect it still won't. Now hook up a jumper from the rear fuse to the wire around the #30 pin, pump should cone on for the 1.5 second. If it does, then you have a connectivity issue with pin #30 to the trace that comes from the fuse. I seem to remember that you have/had an issue with the heater fan/blower also? It could be as simple as the fuse holder to trace is not getting good contact. When I had mine out years ago, I carefully wire brushed each fuse holder and lightly soldered them to the rivet head. I had no more issues after that.
Tom

[jk76.914]

Warren,
I agree, you are getting very close to the problem here. Actually read the whole post first and try cleaning up the fuseholder to trace rivet area. Sometimes just cleaning and moving this area can regain good contact.
Here is the next test I would do to confirm that pin #30 of the fuel pump relay socket has a connectivity issue. Remove the relay itself and wrap a small wire around the #30 pin, reinsert the relay back into the socket with the small wire sticking out, ( a small paper clip could be used also or some small solid conductor wire), now try the key on - pump should run for 1.5 sec. It didn't before and expect it still won't. Now hook up a jumper from the rear fuse to the wire around the #30 pin, pump should cone on for the 1.5 second. If it does, then you have a connectivity issue with pin #30 to the trace that comes from the fuse. I seem to remember that you have/had an issue with the heater fan/blower also? It could be as simple as the fuse holder to trace is not getting good contact. When I had mine out years ago, I carefully wire brushed each fuse holder and lightly soldered them to the rivet head. I had no more issues after that.
Tom

Hey guys, This post save me a bunch of time. I had the same problem- car restarted then died on Friday morning at the Staples store parking lot. I got it flatbedded back to the house, then came in to research the symptoms, and found this thread. I got to this part, and tried the small wire test- the pump ran for 1.5 seconds, then the car started, and ran with no problem!!! I ended up soldering a wire to one end of the fuse, and the other end to the pin on the relay. Installed them both and the car's running fine. Since this wire just parallels the trace under the relay board, I don't see any reason I can't leave it in place for the season, and then remove/rebuild the relay board as my next winter's project.

Thanks for the writeup!

Jim