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MikeM |
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#1
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Senior Member ![]() ![]() ![]() Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada ![]() |
Hi guys...
I have a no start condition on my 74 2.0 liter,D-jet. Seems like the fuel pump is not running. As per my crappy manual, I have checked for power at pins 87 and 86 where the pump relay plugs in. There is no power at either pin with the key on. Manual says if that is the case, then start checking ignition wiring. Obviously, I'm missing something. Swapped out relays with no luck also. Any help really appreciated.... Mike |
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JRust |
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#2
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 6,316 Joined: 10-January 03 From: Albany Oregon Member No.: 129 Region Association: Pacific Northwest ![]() ![]() |
Hi guys... I have a no start condition on my 74 2.0 liter,D-jet. Seems like the fuel pump is not running. As per my crappy manual, I have checked for power at pins 87 and 86 where the pump relay plugs in. There is no power at either pin with the key on. Manual says if that is the case, then start checking ignition wiring. Obviously, I'm missing something. Swapped out relays with no luck also. Any help really appreciated.... Mike There is a fuse on the relay board also. If that isn't blown try hotwiring the pump. Run a positive lead down from your coil. Take a negative from the car then try to start it. Works great off the coil as it still only get's power when you turn on the key. If it still doesn't work you have a faulty pump |
76-914 |
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#3
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Repeat Offender & Resident Subaru Antagonist ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 13,700 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California ![]() ![]() |
use this and you will nail it.
http://members.rennlist.com/pbanders/FPChecklist_frame.htm |
Tom |
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#4
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None ![]() |
Mike,
Before you go running wires here and there, try the following and get back to us. 1- check for power at pin #30 of the fuel pump relay, third relay from front. if power, move on to #2 if no power, check the rear fuse just in front of the frontmost relay for power , both sides to ground for 12 volts. Power to either? If you have power to the right side but not left side, check the fuse. 2- check for power to pin 85 of the fuel pump relay with the key switch to on. No power, check power relay, second relay back from the front. Check these and let us know. Tom |
stuttgart46 |
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#5
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Member ![]() ![]() Group: Members Posts: 305 Joined: 17-December 07 From: Santa Monica, CA Member No.: 8,474 Region Association: None ![]() |
You may want to check your relay as well.
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MikeM |
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#6
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Senior Member ![]() ![]() ![]() Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada ![]() |
Thanks for the suggestions guys...
Tom, how do I check the power relay? The car died at a friends place and we pushed it into her garage. I'll have to tow it home for further investigation. I'll try to get to it asap... Thanks. |
Tom |
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#7
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None ![]() |
Mike,
To check the relay/relays you can use a multimeter on ohms scale between pins 30 and 87, should read open with no power. When power is applied to 85 and 86, then the reading between 30 and 87 should be 0 + or - an ohm or 2. You can use a different relay not being used to temporarily replace the power relay, such as the 4 th realy, which is your heater blower relay, or, one of the round can style ( they all look the same) headlight relays. Tom |
MikeM |
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#8
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Senior Member ![]() ![]() ![]() Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada ![]() |
Tom...I've swapped around relays with no luck.
I think the pump has called it quits. But I can't get under it to jump the fuel pump. The pump has been moved up front under the car. Mike |
MikeM |
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#9
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Senior Member ![]() ![]() ![]() Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada ![]() |
Did a little more trouble shooting tonight. I have power at pin 30 ONLY of the fuel pump relay. Not sure what that means. Also, we found the wires that the P.O. used to extend the fuel pump wiring from the factory pump location to the front of the car.
We cut those wires and gave them 12 volts and ground and still nothing from the pump. So now it looks like maybe something shorted out and took out the fuel pump. What concerns me is that there is only power to one pin of the relay.... Thoughts? Thanks, Mike |
Tom |
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#10
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None ![]() |
Mike,
So you have no power to pin #85 of the fuel pump relay socket with the power relay in and the key switch to on? Try a couple of jumpers on the relays to check them for operation as in my earlier post. You can also spread the male pins a little to ensure good contact in the socket. Just use a knife and gently spread the four pieces apart slightly. Sounds like your fuel pump failed, but I don't understand why that would cause your relay board to suddenly have issues unless possibly the fuel pump overloaded the circuits and caused some otherwise hidden issues to appear. These electrical circuits are pretty old and can give strange indications. Just take it one step at a time and we can find the problem. Tom |
MikeM |
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#11
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Senior Member ![]() ![]() ![]() Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada ![]() |
Tom...that's correct, no power to pin 85. Only to pin 30. I don't understand what you mean by using jumpers. Am I jumping from the power relay to the pump relay?
Thanks so much for your help... Mike |
MikeM |
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#12
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Senior Member ![]() ![]() ![]() Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada ![]() |
One more question....assuming I need a new fuel pump, which pump are you guys using to replace the factory unit? 74 2.0 liter. D-Jet.
Thanks, Mike |
TheCabinetmaker |
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#13
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I drive my car everyday ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,336 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 ![]() |
Since its already relocated to the front, use the 75/76 pump. New 3 port pumps are approaching 400.00
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Tom |
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#14
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None ![]() |
I agree with Curt on the later pumps.
As for testing the relays here are a couple of pics. + to 85, negative to 86. Meter leads yellow to 87, white to 30. No power = open Power applied = 0 + OR - a couple of ohms. You can take the top off of these and try to repair. I have done a couple. The very fine wire from post 85 or 86 can come unsoldered. By resoldering, the relay is good again. Tom Attached thumbnail(s) ![]() ![]() ![]() |
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