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Need more help....

  • Thread starter Thread starter ras50gt
  • Start date Start date Dec 31, 2006

ras50gt

Member
Oct 25, 2005
200
2
19
Dec 31, 2006
#1
  • Dec 31, 2006
  • #1
So I finally figured out some of the electrical problems and fuel issue, put in an electrical fuel pump, a big thanks to all those that helped me out. Well, I have two more issues I need help with.

First- Im having a problem with the electric fuel pump, I connected the positive wire from the fuel pump to the external resistor, the side which the green ignition wire goes to. It worked once when turning the key, but then wouldnt work again. I have also tried connecting the fuel pump wire to the positive side of the coil itself, got the same result after a few tries. Then I tried connecting the fuel pump wire directly to the positive side of the battery and it works perfectly every time and the car starts up/runs, but of course having the pump connected directly to the batt means it stays on with the ignition off. Any ideas why connecting the fuel pump to the external coil resistor or the pos side of the coil isn't working? Or what I can do or try? Also, to make sure I have this all hooked up right, I have the green wire from the ignition hooked up to one side of the external resistor(ballast) then a wire from the other end of the external resistor to the positive side of the coil, then the black wire from the distributor to the negative side of the coil. I think this is all right and the car does start up so I'm completely unsure why the pump wont run off the ignition wire????

2nd- I had the car up and running, fuel pump wire connected directly to the battery cause thats the only way it stays on and pumping... I set the timing, then I tried putting the car into gear. I put it into reverse and then put on the gas, seemed to take a second or two of high throttle but then the car started going in reverse, so I slowly went in reverse. Then I tried putting it into drive, but the car goes no where, tried 1 and 2 also with same results, seems like its in neutral and thought I would feel the car engage but doesnt seem like it. Did I completely f*** something up, maybe when installing the engine, what could this be?
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Dec 31, 2006
#2
  • Dec 31, 2006
  • #2
ras50gt said:
First- Im having a problem with the electric fuel pump, I connected the positive wire from the fuel pump to the external resistor, the side which the green ignition wire goes to. It worked once when turning the key, but then wouldnt work again. I have also tried connecting the fuel pump wire to the positive side of the coil itself, got the same result after a few tries. Then I tried connecting the fuel pump wire directly to the positive side of the battery and it works perfectly every time and the car starts up/runs, but of course having the pump connected directly to the batt means it stays on with the ignition off. Any ideas why connecting the fuel pump to the external coil resistor or the pos side of the coil isn't working? Or what I can do or try? Also, to make sure I have this all hooked up right, I have the green wire from the ignition hooked up to one side of the external resistor(ballast) then a wire from the other end of the external resistor to the positive side of the coil, then the black wire from the distributor to the negative side of the coil. I think this is all right and the car does start up so I'm completely unsure why the pump wont run off the ignition wire????
Click to expand...

DO NOT connect the fuel pump to the coil as it draws too much energy, especially since you are using that wire to power the pump itself. i am surprised that is worked once even for a couple of seconds. you need a dedicated power feed to the pump, and it is best to run that feed through a relay for best results. find a 12v switched source under the hood to trigger the relay, that is NOT connected to the ignition system.

ras50gt said:
2nd- I had the car up and running, fuel pump wire connected directly to the battery cause thats the only way it stays on and pumping... I set the timing, then I tried putting the car into gear. I put it into reverse and then put on the gas, seemed to take a second or two of high throttle but then the car started going in reverse, so I slowly went in reverse. Then I tried putting it into drive, but the car goes no where, tried 1 and 2 also with same results, seems like its in neutral and thought I would feel the car engage but doesnt seem like it. Did I completely f*** something up, maybe when installing the engine, what could this be?
Click to expand...

make sure the vacuum line to the modulator is hooked up to a full time vacuum source and not pinched.
 

ras50gt

Member
Oct 25, 2005
200
2
19
Dec 31, 2006
#3
  • Dec 31, 2006
  • #3
So for the fuel pump issue, can I just run a wire directly from the positive batt post with an inline fuse into the car and have an on and off switch? What other 12v connections could i use? I read a thread about using the "key on" wire, do you know what color that is/where it is? Thanks, I'm going to be looking at the vacuum line soon, hopefully its something simple.
 

ras50gt

Member
Oct 25, 2005
200
2
19
Jan 1, 2007
#4
  • Jan 1, 2007
  • #4
Good or bad idea: to hook up the electric fuel pump to the positive side of the starter solenoid with an on/off switch to turn the pump on/off??? If a bad idea, what other "key on" wires do you suggest?
 
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