Fuel pump connector electrical problem

[Hakmak]

So I'm having issues with my pump I dont believe the pump is bad but I'm not sure. I've been searching everywhere but cannot find anyone who had this same issue. Here my issue : I connected the 12v straight from the battery onto the wire coming from the fuel pump connector (see attachment). I successfully tested it see if I was getting voltage from to the wire. As soon as I plugged the connector in, the voltage just dropped off completely....WDF???!! What would make this happen? If my pump was bad I would still get voltage in the wire. Does any one have any idea? I've been running with a rewired pump for about 3 months so I know I did that correctly.

Forgot this

Forgot this

 

[jonathanfl]

Check the ground circuit, you may have a bad ground if its dropping out once there is a load

 

[Hakmak]

I thought bout that so I checked the ground wires and both seem good. I checked them by connecting the positive lead from the millimeter to the battery then ground lead to both ground points to see if I get a reading, which I do. Any other ideas? Or do you mean the ground circuit on the fuel pump itself?

 

[jonathanfl]

Just because your dmm gets a reading does not mean the your ground is good. A bad ground will cause a failure. Find out what amount of load that circuit is making and you can make a load with a light. Or find a good ground and introduce it to the circuit to see if the pump works.

Also check the connectors terminal ends if theres debris that will change the resistance also causing you issues

While your there also ohm out the pump to make sure theres no ol

 

[Hakmak]

Thanks for the info I'll review the grounds again. I'm getting 90 ohms on the pump relay. ..I read somewhere there is suppose to be 56-60 ohms (or something like that)on the relay. .I bought 2 relays one from autozone and one from radioshack. They both read 90 ohms.

 

[jonathanfl]

Also check the terminal end at the pump to the frame of the car to see if you have a wire run through grounding out before its supposed to.

 

[Hakmak]

Update: So I checked all my ground connections and they all seem to be rock solid I even used a wire brush bit on my drill to make them shiny and clean. Still no power when the connector is attached to the pump connector. So I started the process of removing the pump when I ran into a snag. The rubber feed line under the car keeps twisting as I try to remove it from the hard line. I stopped because I did want to break the rubber but I'm starting to think I should just twist it anyway then replace the rubber piece if it breaks. I'm had it up to here at this point! I just want to find the damn issue.

So I pulled the pump, nothing looks out of the ordinary. The only other thing I can thing of now is there might be some damage in the pump electrical connector itself. I think I'm going to cave in and buy a new pump. Its a pricey way to trouble shoot but this is my last resort.

 

[Hakmak]

So it looks like I no choice but to pick up a wally 255 at this point. I'll also need to get a new rubber feed line for the pump. I'm give an update on this in about 3wks. Thanks for all the help thus far guys.

 

[Hakmak]

So it looks like I close to figuring out what the dam issue is. I installed the new wally 255 and still has the same issue but this I knew because it was obvious that my issue was electrical. So I took the old pump and pulled it up directly using the power wire off of the relay coming straight from the battery and it did respond. So I brought it to the front of the car and hooked it up straight to the battery and Walla.....it came on...but now here is where it gets strange...I took it back to the back and connected the wire of the relay again and guess what...it started working. So I proceeded to test the newly installed 255 and that too cane on. I connected everything back on to the relay and it started right up. So now I like...wtf?? Ran the car for about 20min...shut off...then tried to start up...nothing. So I did the same thing as described above. Tested the old pump with the wires in the back...nothing happens...then I took it to the front it started working, took it to the back and that started working....So that's where I am now.....it's hard to predict when it's going to stop working. I figured it might be the battery terminals so I tighten them before I tested the second time but it didn't come on until I connected it to the battery itself first.....idk what the he'll is going on

 

[Hakmak]

SOLVED!!!!! My problem was the god damn fuse holder, the connector was super lose so and got worse as I kept removing the fuse to check for breaks. But now my engine fuse blew after idling for about 10-15 minutes, good thing I bought and extra just in case drove to queens which took about 20 minutes without blowing the Engine fuse again. Now I have to look up what can cause the engine fuse to blow. I dont know if I should get a new fuse holder or new 30A fuse. But man this car pulls now. Only thing is that its starting to sputter up top so I think I may have a boost leak somewhere.