 No power to fuel pump, seems to be a common problem around here |
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| warrenoliver |
 May 24 2013, 10:04 PM
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Member  Group: Members Posts: 363 Joined: 11-November 06 From: McFarland, Wisconsin Member No.: 7,199 Region Association: Upper MidWest  |
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? |
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| warrenoliver |
May 27 2013, 07:28 PM
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Member Group: Members Posts: 363 Joined: 11-November 06 From: McFarland, Wisconsin Member No.: 7,199 Region Association: Upper MidWest |
I think I have finally tracked it down. With the key on or off, I have 12V to the 30 pin which should be normal. With the key on, I have 12V to the 85 pin which is coming from the power supply relay. These are measured on my digital multimeter. If I jump from the 85 socket, the pump runs. If I jump from the 30 socket, the pump doesn't run. So I tested with a headlight bulb to see if i could draw power from the sockets. The 85 socket tests great, the 30 socket does not light the bulb. Since the 30 socket gets its power from the fuse, I checked with the fuse holder and it lights the bulb. So this leads me to believe that there is a break somewhere between the fuse holder and the 30 socket of the relay board. Until I get a good used relay board, am using a jumper under the fuel pump relay between the 85 and 87 pin - pump runs good.
I want to thank everyone for helping - especially Tom, Dave Darling, and John H (IMG:style_emoticons/default/beerchug.gif) Warren |
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Posts in this topic
warrenoliver No power to fuel pump May 24 2013, 10:04 PM
Tom Jumpering pin 87 of the fuel pump relay is the sam... May 25 2013, 03:46 AM
warrenoliver Tom,
When I jumper from the fuse to 87 of the fue... May 25 2013, 07:17 AM warrenoliver I tested the heater fan circuit also. The fan run... May 25 2013, 08:00 AM warrenoliver I spread the pins on the relays and cleaned the co... May 25 2013, 08:37 AM Dave_Darling Both the heater fan blower and the fuel pump relay... May 25 2013, 08:45 AM warrenoliver Thanks Dave,
The relays are good. When i have the... May 25 2013, 09:37 AM Dave_Darling
When i have the power supply relay in, and the ke... May 26 2013, 11:26 AM Jon H. Do you still hear the clicking coming from the TPS... May 25 2013, 04:20 AM Cap'n Krusty Install the 2 headlight motor relays in the FI con... May 25 2013, 07:36 AM warrenoliver I tried that previously but I just tried it again ... May 25 2013, 09:23 AM 76-914 . Here ya go http://members.rennlist.com/... May 25 2013, 08:09 AM warrenoliver Thanks for the Anders troubleshooting tips. When ... May 25 2013, 09:43 AM Bob L.
Thanks for the Anders troubleshooting tips. When... May 25 2013, 10:26 AM warrenoliver OMG, thanks Dave for the pictures. Without those,... May 25 2013, 12:17 PM Bob L.
OMG, thanks Dave for the pictures. Without those... May 25 2013, 12:50 PM warrenoliver Oops, sorry! Thanks Bob.
May 25 2013, 02:52 PM Tom Warren,
Sorry to not answer back sooner. I have... May 25 2013, 03:39 PM warrenoliver Tom,
I think you may be right but I just don... May 25 2013, 04:42 PM Tom Warren,
From what you have said, it doesn't... May 25 2013, 04:59 PM warrenoliver Tom,
I unplugged the AAR and it didn't help.
... May 25 2013, 07:00 PM Jon H. Don't forget, he is also not hearing the injec... May 25 2013, 05:22 PM warrenoliver I can hear clicking when I reseat the relays but I... May 25 2013, 06:42 PM Jon H.
I can hear clicking when I reseat the relays but ... May 25 2013, 07:02 PM warrenoliver Yes, when I jumper from the fuse to the 86 socket ... May 25 2013, 07:21 PM Jon H.
Yes, when I jumper from the fuse to the 86 socket... May 25 2013, 07:52 PM warrenoliver Thanks for all your help guys. Anyone know where I... May 25 2013, 07:55 PM Jon H.
Thanks for all your help guys. Anyone know where ... May 26 2013, 05:55 AM Tom Warren,
That could very well be the problem. ... May 25 2013, 07:47 PM Tom Warren,
I agree, you are getting very close to ... May 26 2013, 12:24 PM warrenoliver Some great ideas there Tom. I really appreciate e... May 26 2013, 03:31 PM jk76.914
Warren,
I agree, you are getting very close to... May 17 2015, 05:23 PM Tom Warren,
The #30 pin for the two relays are from... May 26 2013, 05:03 PM warrenoliver I must be missing something then. When i look at ... May 27 2013, 09:05 AM Tom Warren,
Take another look. Follow the lines ... May 27 2013, 09:45 AM warrenoliver Tom,
Aha! I think you may be on to it. Even... May 27 2013, 12:22 PM warrenoliver DAMN!!!!!! This thing is... May 27 2013, 03:36 PM Jon H. I find these electrical Gremlins to be the most fr... May 28 2013, 04:17 AM Tom Warren,
Very happy I could help. Glad things ... May 28 2013, 10:56 AM revhi109 I am also having issues with my fuel pump not comi... Mar 30 2015, 10:12 AM warrenoliver
I am also having issues with my fuel pump not com... Apr 1 2015, 07:20 PM flylarry If the relay works and a jumper between the fuse a... May 17 2015, 08:15 PM |
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