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hey all I am having trouble with replacing my fuel pump I used a universal and wired it in every which way I can fuses are fine I’m not sure about the relay but nothing has worked just wondering if someone could help me out here
Why did you replace original pump Have you tested with a multimeter to be certain you have power and ground AT the pump. What kind of pump did you install,brand? There are a lot of poor quality parts out there.
Without knowing if you have power and ground to complete the circuit at pump you can't know if the original or replacement pump is bad. How are you checking fuses,looking at them? Get a multimetyer if you don't have one and check fuses with it and wiring at pump and then look at relay as cause in that order . If you're not sure how to use multimeter to test these things,post back as so and i'll be happy to give you instructions on how to use multimeter to diagnose your problem.
I have a multi meter didn’t use it yet to figure any of it out and it was some small brand at a auto parts store I bought another one online seemed to be a better brand just Incase the replacement was a faulty one but I wasn’t getting fuel to the carb just swapped engine from an 82 to my 84 I’m just seeing if I could find any other suggestions
Power won't be sent to the pump until the vehicle is running. The emissions computer disables it. You can jump the fuel pump relay to get around this. I don't have the link but there is a thread here that shows you how to bypass the relay and get the pump to turn on.
Power won't be sent to the pump until the vehicle is running. The emissions computer disables it. You can jump the fuel pump relay to get around this. I don't have the link but there is a thread here that shows you how to bypass the relay and get the pump to turn on.
Yeah, what he said ^^^ This had me all confused when I replaced my FP. There are threads on the forum to jumper the relay so that the pump will run with the ignition "on" but motor not running. Very helpful for priming new lines and carbs. the connector you want to unplug is up under the driver's side dash, attached to the right side of steering column. if you can lay on your back/shoulders to look up at it the first time, you'll be able to find it again later by feel. i just left the jumper in place of the plug, and everything works and drives fine. I've been trying several carbs and intakes lately, so it comes in handy. Here are some pics.
This ^^^ is looking up under an FC's dash (see the steering column on the left?). I think the plug is a little different but the location and mounting is the same on your car. .
i just left the jumper in place of the plug, and everything works and drives fine. I've been trying several carbs and intakes lately, so it comes in handy.
I would advise against leaving it jumped long-term. It's a fail safe allowing the ECU to turn the pump off if the engine stops.
10-4. I wasn't trying to give dangerous advice - I'm actively working on my fuel system and it's convenient to pull the jumper and crank the engine to drain the fuel bowls before pulling a carb. Once I have everything sorted I'll reconnect the relay plug.
Your picture is of the wiring on the left of steering column. The Relay and plug I mentioned pulling is on the right side of column - I can see the mounting tab/screw in your picture. Look at this .......
The plug/relay is under a rubber boot - not sure why. But there's a typical squeeze-to-open tab on one side like most electrical connectors on the car. I think I can see it on the right side of the relay (in the rubber boot) in my pic, and I think you just squeeze it through the boot while gently pulling the plug out. The jumper has to go in the two slots as I show here, and was shown in the sketch a few posts up. After you do that power will go to the pump anytime you turn the ignition key to "on" (the normal "car is running") position. Just like if you wanted to turn the radio on but not start the engine. It will also keep pumping as you start the car.
As chuyler1 mentioned above, this is not 100% safe to leave permanently jumpered, because if you crash into a pole the pump is going to keep pumping, even if your engine is in the next county. IE - fire hazard. But to prime your lines to the carb, or simply check if your new pump works, this is the way to do it without cranking your motor over. i have been trying different carb and intake and regulator setups, and like to pull the jumper and turn the key, to run the engine off the fuel in the bowls to drain the carb before removing (without the pump pushing any more fuel). Holy run on sentence.
Any specific reason why you replaced the OEM pump with an aftermarket?
The Mazda OEM pump is amazing quality, last for decades, and will support enough fuel for any power a stock ported engine could make. It is available from any Mazda dealership and can be ordered in a few days.
What other modifications have you done to the fuel system to support the aftermarket pump? I am worried that you will figure out the wiring problems only to run into other fuel system problems, pressure too high, poor pump life, carb issues etc.
