fuel relay not getting power so......
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Launching!
Joined: Dec 2003
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From: Tifton, Gerogia
fuel relay not getting power so...... my fuel relay is not getting any power, so could i just wire up my pump to an
ignition source, or is there some other way to rig it up with the pump running only when the engine is running?
ignition source, or is there some other way to rig it up with the pump running only when the engine is running?
why is the relay not getting power?
the fuel pump has to go thru a relay! you could hook it up to a oil psi swtch but it will have an extended crank time unless the engine builds oil psi very fast.
kevin
the fuel pump has to go thru a relay! you could hook it up to a oil psi swtch but it will have an extended crank time unless the engine builds oil psi very fast.
kevin
Thread Starter
Launching!
Joined: Dec 2003
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From: Tifton, Gerogia
i thank i may have pulled a wire loose in the bulk harnes, is why its not getting any power to the relay, well can anyone tell me how to wire up some other kind of relay for the pump,
You'd rather fix the stock relay logic, there's not a clean way to reproduce the safety feature of it only running when the engine is spinning. Wreck the car w/ a ghetto rig fuel pump relay, it keeps running, you risk big fire.
Not sure who did your wiring, but bear in mind the fuel pump relay receives 12VDC trigger from the PCM if I recall right...unlike the fans where the PCM switches ground.
Not sure who did your wiring, but bear in mind the fuel pump relay receives 12VDC trigger from the PCM if I recall right...unlike the fans where the PCM switches ground.
Teching In
Joined: Feb 2005
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Just remember the ECM will only pulse the fuel pump relay for 2 seconds with ignition on engine not running. And if you wish to reset the cycle you need to turn off the ignition for about 10 seconds. As stated the PCM sends positive current to the FP relay, all other subsystems control relays via the ground side. Surely listen for the relay to cycle on for two seconds then off so you will here two clicks on and off. In stock factory setups this type of ECM failure is rare so its likely something else.
Thread Starter
Launching!
Joined: Dec 2003
Posts: 288
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From: Tifton, Gerogia
okay the harness im using is a painless, and i had setup the engine and got it running but i broke the trans pump and had to pull every thing back out, now i have every thing back in, this painless harness is a very simple hookup, i tested the wires going to the relay and there not getting any power, i tired using another PCM and still nothing, i have to do somthing im tired of trouble shooting this damn ls1 converstion, its not worth it!
Originally Posted by sr_ryan1
okay the harness im using is a painless, and i had setup the engine and got it running but i broke the trans pump and had to pull every thing back out, now i have every thing back in, this painless harness is a very simple hookup, i tested the wires going to the relay and there not getting any power, i tired using another PCM and still nothing, i have to do somthing im tired of trouble shooting this damn ls1 converstion, its not worth it!
If you're getting no 12VDC to the service lug (the one the relay closes to the fuel pump), time to check fuses or fusible links. Maybe a call to Painless tech support to ask where the protection for the fuel pump relay is located will help.
I can tell attention to detail isn't your happy place, but that's what it will take to get it running again and keep it running this time. (hint, check the spelling of your home state)
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The relay is powered up when the key is in the on position. you need to see if the wire is connected to your ignition. it will send current to your relay. also, make sure all things are grounded. the conversion does suck at times but after all the money gets spent and forgoten, it will be worth it. good luck!
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get a multimeter. unplug the relay. push the black tester into the ground for the relay.. set the meter to Olms and touch the red wire to a ground (the engine block, chassis, whatever)... if its good (reads 0.00) then leave the black one in the connector and move on. if not, then thats your problem.
1. check if theres power going to the fuel pump turn on wire when you first turn the key on. no? thats your problem. trace that wire. (painless harness = 98 PCM.. i dont have the chart for that one or id tell ya the pin.) yes? go on to step 2
2. main FP power going into the relay connector. does it have power? no? thats your problem. yes? move on to step 3
3. you have power, so lets check the relay. take a piece of wire (thicker is better) and shove it into one of the fuel pump wire connector... touch the other one to the positive lead. yea, it might spark.. no it wont shock you, and you only have to do it for a second.... if the fuel pump kicks on... the relay is bad... if it doesnt, you have a bad connection to the fuel pump, or bad fuel pump.. move to step 4
4. shove the jumper wire in all the way... put the connector somewhere where it wont short/fall...go to the back of the car, and see if the fuel pump connector in the back sees power. if it doesnt, the wire is broke... if it does, the fuel pump is bad...
that should do it.
if you just relax, and TROUBLESHOOT the problem, you can solve things like this so fast that they arnt even problems.
1. check if theres power going to the fuel pump turn on wire when you first turn the key on. no? thats your problem. trace that wire. (painless harness = 98 PCM.. i dont have the chart for that one or id tell ya the pin.) yes? go on to step 2
2. main FP power going into the relay connector. does it have power? no? thats your problem. yes? move on to step 3
3. you have power, so lets check the relay. take a piece of wire (thicker is better) and shove it into one of the fuel pump wire connector... touch the other one to the positive lead. yea, it might spark.. no it wont shock you, and you only have to do it for a second.... if the fuel pump kicks on... the relay is bad... if it doesnt, you have a bad connection to the fuel pump, or bad fuel pump.. move to step 4
4. shove the jumper wire in all the way... put the connector somewhere where it wont short/fall...go to the back of the car, and see if the fuel pump connector in the back sees power. if it doesnt, the wire is broke... if it does, the fuel pump is bad...
that should do it.
if you just relax, and TROUBLESHOOT the problem, you can solve things like this so fast that they arnt even problems.
