My fuel pump was running continuously with the key in the "on" position, so I found the old thread dealing with wiring the dual relay properly and testing the Air Flow Sensor and followed the diagnostics and testing stated in there. Air Flow Sensor tested fine, wiring as specified, and now the pump runs with no key in the ignition. I think the pump was re-wired to run through the ignition switch, which I know was wrong. Now I think I may have a bad ignition side on the dual relay. The relay has two numbers on it. Ignition side says 071 906 059. The FI side says 0332 514 129. All connectors are designated on the relay with the same numbers in the same positions as the 120 that the old thread used. The old thread was great to follow as long as things went as planned. In this case, the result was a failure to operate correctly once all the wiring was reconfigured. Any help out there?

Sorry, I'm too lazy to re-read that old thread. Plus, not all problems fit the same mold, yours may take a different direction. I guess my first question would be, does the car run? The fuel pump is turned on by 2 sources, one being the contacts within the AFM (which energizes the dual relay) and the other being the ignition switch in the "start" position, which also energizes the dual relay. You say the fuel pump runs, as soon as you turn the key to the "on" position? If so, let's try to isolate the problem. The fuel pump should not be activated with the ignition switch in the "on" position, unless the car is running. Go ahead and turn the key to the "on" position, as you stated earlier, the fuel pump turns on. Pull the connector off the AirFlow meter, does the pump turn off? If it doesn't turn off, yank out the dual relay. After yanking the dual relay, did the fuel pump turn off? If so, measure pin 86a at the dual relay connector, (it should be the yellow wire). Do you have 12vdc here? Can you post a pics of your dual relay, and your setup?

I will have to put the wiring back to the way it was, which I will do this morning. I will warn you that the car has "re-wired" by PO, so no guarantees that proper wires of the proper color will be present. My dual relay has the white connector for the ECU, but the ignition side black connector is not present. Wires on that side of the relay are spade connected directly to the relay terminals.

I'll put the wiring back the way it was, conduct the two tests you recommended, and take pictures of the relay and post them. Thank you fr your help.

Interesting, but it's fine, connector no connector, it doesn't bother me. Electrically it will all be the same at the end. Leave it as is, just take a picture of the ignition side and tell me what you have for lose wires. With the way it's setup, is there a jumper on the relay from 88y to 88z?

Just tested the wires that were originally hooked up to the fuel pump -relay and AFM disconnected, got zero volts with ignition off, 12 volts with ignition on. Looks to me that the pump was re-wired through the ignition switch.

Never answered your question about whether or not it was running to begin with. The answer is Yes, but very badly. Found lots of gas in with the oil in the crankcase, even blew into the exhaust which would smoke heavily once it got hot. All four plugs wet with gas and a little carbon, but not crusty as if burning oil.

Back to the relay. On the ignition side I have a wire from the battery positive terminal that I can connect to 88z and it has the jumper on it that I can connect to 88y. Just took pictures of the relay and need to upload them onto the computer and post them. Just a note, the way it was originally wired, there was no wire hooked up from 86 to the fuel pump. In fact there was no wire leaving the ignition side of the relay and going to the pump at all. I'll send you the pics.

Pin 86 on the relay works with the thermotime switch. Pin 88d is what powers the fuel pump, it should be a black wire with red stripe. It would be good to know if you have 12vdc on that wire. Disconnect that wire from the relay, and see if the fuel pump turns off. If it doesn't turn off, measure if you have 12 volts on that black/red wire.

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I just read your little side note at the end, you really have no other wires? On that side of the dual relay you should have a big red wire on pin 88z that goes to the battery, then a jumper from 88z to 88y (this you do have). The others, you should have a yellow wire going to pin 86a (ignition "start" 12vdc source). Then a brown wire going to pin 85 (ground). Next will be a smaller gauge black wire on pin 86c (ignition "on" 12vdc source). Lastly, you should have a bigger black wire with red stripe going to pin 88d (powers up the fuel pump). Without these wires attached, I don't see how the car could even start. That brown wire feeds ground for both parts of the relay. Without a ground wire supplying the dual relay, pin 88a and 88b will never make contact, thus no power to ECU or the resistor pack. Maybe these missing wires are cut back at the harness, do you have a harness that plugs into the 12 pin relay board connector? If the wires are merely cut back, perhaps a quick trip to Radio Shack might be the answer. Also, where is the fuel pump located on this car? I remember reading somewhere that this is a 1.7L car with a 1.8 Ljet retrofit? If this is the case, which style fuel pump are you using?

Sorry for the confusion. I have the other wires, but had everything disconnected except for the 88z and 88y jumper, because that's where you had me starting from. I have a ground coming off the motor on terminal 85. I have a 12 volt wire coming off the distributor + which is hot with ignition on, this is on terminal 86c. There was no wire on terminal 88d going to the fuel pump, so I made one up and connected it to the + side of the pump, which is located in the engine compartment down low in the corner by the battery. I have the pump out now as I'm getting ready to order SS fuel lines and wanted it out for the testing anyway. I also connected a ground wire from the pump - to ground. There was no yellow wire on 86a which as I understand should be a source that is only hot 12 volts when the starter is turning. I traced the yellow starter wire back from the solenoid, found a splice where it connected with a purple wire in the engine compartent "harness" and installed a jumper to terminal 86a, after confirming that it is only hot 12 volts when starter is cranking. With everything hooked up that way, and with the white FI side connector installed, pump runs with ignition off, as if the ignition side relay is either stuck or shorted closed. Does that make sense? I can show you pictures of the relay with everything hooked up if you like. Pump is nrmal Bosch high pressure. Car is a 72 that was originally 1.7 and I think with this L Jetronic setup on it. Motor has been replaced with 75 California code 1.8. Still has catalytic convertor on exhaust from the '75, but the smog pump and evaporative control system are gone. My ECU is plugged in, and the car was running well enough to drive it out of my trailer, up the hill, and into my garage, so the ECU was firing the injectors and the ignition was generating spark. But there were so many air leaks on the intake, it ran terribly, and the pump running when the engine wasn't, was a concern of mine, especially since there was fuel in with the oil in the crankcase. Suspected a leaking injector so pulled the injectors, bench tested them for spray and leaks, but all tested good. Replaced the inner and outer seals, all four inners were cracked. So I'm making progress, but this dual relay thing is a problem, even though I think I now have it wired correctly. Thanks

Correction, wire on 86c is coming off of + terminal of the coil, not the distributor as stated in the last thread.

Much more sense! So the fuel pump has a new wire going to 88d. To recap, with the ignition to the on position, the fuel pump runs. Let's check for voltage at pin 86a with the ignition switch at the "on" position. You should have 0 volts present. If you have 0 volts at 86a, then remove the dual relay and ohm out pin 88y to 88d, you should have infinite resistance.

Yes, the fuel pump has a new wire to its + terminal and a new wire from the - terminal to ground. Seems like the ground for the pump can be simply mounting the metal body of it to the car, but I have it out so I ran the ground wire to be sure. And not only does the pump run when the ignition is in the on position, it runs when the ignition is in the off position as well. I'll do the voltage and resistance checks this morning.

Ok, zero volts at 86a with ignition on and off. This wire should only be hot 12 volts when cranking, correct? Pulled relay and checked resistance between 88y and 88d. Got zero resistance, meaning I have continuity between these two terminals. Here are some pictures to document
Meter not connected with leads apart reading 1ohm meaning infinite resistance and open circuit.
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Meter with leads touching, reading zero ohms, meaning continuous circuit.
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Meter attached to relay, reading zero ohms, meaning continuous circuit.
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A couple pictures of my fuel pump, since you asked about it.
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Good to hear 0 voltage on 86a, it means that your car wiring isn't screwed up. Bad news having 0 ohms across pin 88y and 88d. The internal contacts within the dual relay should be open and have infinite resistance. This explains why the fuel pump runs with the key in or out of the ignition switch. You may be able to open up the dual relay, and see why the contact is stuck shut, or buy a new dual relay.

I will try to open it up and see what's stuck inside. Do you know who sells these relays? I have looked at autoatlanta and pelican and can't seem to find them on either site. Would NAPA carry something like this? Maybe my local Import Parts Warehouse guys might have one.

Thank you for your help.

Opened up the relay and here's what I found.
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Corrosion on the ignition side of the relay and a broken/missing spring that normally keeps the circuit open until current is applied and the coil pulls it closed. That's why the circuit was showing continuity. Don't know if I can find a little spring to replace the missing one, but it's worth a shot. As long as I can clean it up and it still works, I can always use it as a spare if I buy a new one. Problem seems to be diagnosed and soon to be solved!

Yah, you're correct with the spring operation. That spring holds the contacts normally open. I have attached some crappy pics of a spare I had laying around.

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I had marked in red the contact area

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This is what the measurement should look like with a working dual relay


sorry about the crappy pics.

Yours looks a lot like mine, crusty in one corner. I cleaned mine up with a Dremel with a soft wire brush, and I think that with a new spring, it should still latch and release. I still would like to buy a new one to be safe. Any idea of who sells them? You have been a great help. If we ever meet, I'm buying the beers!

It was my pleasure. I would give you my spare, but I like to keep that in my glove box, just in-case I'm stuck on some interstate. If you have some old VCR, you could take it apart and find a plethora of springs within. You are on the hunt for a 120 series dual relay. Send Cap'n Krusty a pm, he seems to have a stock pile of parts in his garage. If that fails, post a WTB ad in the classified section. There is some guy currently selling his complete 1.8L system for 150.00. It seems like a good deal, but I couldn't pull the trigger due to the lack of pictures. Best of luck