Problem with ground wire from fuel pump connection to truck frame
I changed the fuel pump on my 1996 GMC Sierra earlier in the year. I cut through my truck bed right above the fuel
pump so I would have easier access to it. For the most part my truck has been fine but I have had problems with the
ground wire coming from the fuel pump. At first I thought it was just the old rusty bolt that grounds the fuel pump
wire to the frame so I switched the bolt out. The newer bolt and nut did okay for awhile then my truck started dying
on me. I would mess with the wire and bolt eventually it would start. So the other day my truck died on me and I had
a hard time to finally getting it started. I used a slightly bigger bolt and nut and thought that would solve that
problem, but I went to start my truck this morning and it wouldn't start. After I got home from work, I messed with the
ground wire coming from the pump and messed with the bolt and nut that keeps it grounded to the frame and I
eventually got it started. Is there anything I can do to fix this for good?
Yes there is. Remove the bolt and sand the area so it bright bare metal. Coat the bare metal with silicone grease. Get two washers and a electrical ring terminal for the wire. Drop a washer on the bolt, then the ring terminal with the ground wire and then the second washer. Grease up the entire assembly to waterproof it and install the bolt into the frame. Use a washer, lock washer and nut to secure it in place.
Exact same thing I would do except for the grease. There is an electric terminal protector that comes out red that repels both water and dirt. I would stick with that.
This is after it was totalled. if you look at the bed I did the exact same thing when I replaced my pump. There was Soo much rust I was afraid to try to drop the tank.
Hey John, what's the name of that red electrical terminal protector stuff? I've been using the di-electric silicone grease for years - mostly because I have a couple of tubes of it. It also works like Rain-X but it takes a lot of polishing to remove the haze.
CRC battery terminal protector is the stuff I use, it comes in a yellow can, it doesn't attract dirt like grease does. They also make a terminal cleaner that turns red when battery acid is present. Kind of like an early warning for batteries that will need replaced soon. I have tubes of the dielectric for tune-ups.
Thank you both for answering my question. I'll try what was recommended.
Btw if you by some odd chance nicked the wire somehow it may be starting to deteriorate from the inside and moving the wire may be making a connection. Just a heads up.
I went ahead and bought a whole new fuel pump. When I took the other one out, I noticed that the gray wire that was inside at the top of the fuel pump, was melted. It was dried bubbled up plastic with bare wires showing. So I put my new one in and now it still won't start. And now my battery is drained from trying to start it so many times. Any ideas? I'm beyond frustrated and any help would be appreciated.
Check the continuity of the wires
Thank you, John. How do I go about checking the continuity of the wires? Last night I read how to reset the ECM by disconnecting the black cable from the battery and then turning head light switch on for a few seconds. After that, I reconnected the black cable back onto the battery and my truck started right up. I test drove it to the end of my road and it died and I haven't been able to get it started since.
You need an ohm meter. Touch one lead to the ground side of the connector and the other lead to the eyelet on the ground wire to find out the resistance to see of the wire is bad. Same with the power wire from the relay to the fuel pump connector.You can also try sliding the wire between two fingers while slightly bending the wire to feel for a soft spot but this may not work due to the fact that it works sometimes so the bad spot isn't real big yet.
It may also be at the pigtail going into the sending unit. You said it was burnt so the connector may be where it has fallen apart. Go to the parts store and see if you can buy a pigtail for the sending unit. Get a pic and head to your local carquest.
I have a 98 Chevy Truck with a similar problem. I recently added a 6 AWG ground wire from my 5 spd trans to the frame and cleaned up the battery ground connection to the block. I plan to add another 6 AWG wire to the body as an additional ground to tie the 3 major components together. FRAME - BLOCK - BODY. The fuel pump is grounded to the FRAME so the theory is that I am adding a secure ground to the FRAME so that all are securely grounded. The ground straps were only 3 bucks each. No great investment for a stable electrically grounded system.
OK I have a 96 Chevy 1500 I just changed fuel pump but still wont.come on only ground going to fuel pump to frame should one go to body changed the relay fuel just wont come one wondering what's going on
I have a 95 that died on me going down the road and the person i got the truck from replaced the fuel pump 2 Times in 4 years. I could not get it started so I let it sit for 2 months.got in it today and it started. Don't want to drive it til I know what the problem is and it is fixed
The battery cleaner and protector come from NAPA
I find that drilling a hole into the frame get copper clad bolts and using # 10 stranded with copper ring terminals has to make a difference. I am in process of doing this now. Daisy chaining your components will strentghen your grounds I am trying to find where relay gets its ground and I think that will answer all this!
A few other points on grounding, also check your starter to frame and body. There should be a ground strap from the starter to the frame, and another from the same bolt to the firewall. These can also cause your fuel pump issues. make sure all are good and clean, electrical grease or CRC as recommended above. Be careful with the ground to body nut, it connects to a copper stud which breaks easily if over tightened, (trust me, I did that, and it's a pain to replace.) Also make sure to use star washers, not flat or lock washers. The star washer actually "bites" into the frame and connector to make a better connection. Hope this helps! Good luck!
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