Hey guys, I don't post too much but I can't find anything specific to this weird problem I'm having, fuel pump is shutting off left me stranded 2X last couple days. Seeing if anyone has any ideas.. 99 S10 5.3 out of a 02 silverado (cam only) new 140amp alternator overdrive pulley, I am getting 14amps to the battery at idle and 13.8 with the fans running (I have dual fans off a SAAB 93 they kick *** but seem to drawl amps like a mother) Anyway, when I get stuck in traffic I know I'm on borrowed time because in 15 min my tach will shut down and 3 min later I lose the fuel pump. which leads me to think its losing voltage. After 10 min or so on the shoulder of the freeway, I get the fuel pump back (walbro 255) it will fire up and drive (still no tach). I park it come back after work and presto, everything works like new! Thought it was a heat issue so I added hood vents and wrapped the headers, that wasn't it. I'm thinking next is a hotwire kit to the pump, then possible a 2nd battery? Maybe new grounds? I don't know, chasing ghosts at this point. Thanks BTW

 

I think you mean 14 volts not amps. Seems the alternator is putting out but there is a choke point somewhere in the wiring. Yes, fans eat electricity. Lets start at the battery. Positive cable (good stuff with LOTS of strands) goes to the solenoid. Both ends of the cable have quality terminals crimped on with shrink tubing over them. Next is the ground cable. Same as the positive cable, quality cable that runs from the battery to the mounting bolt of the starter and not to the frame. Alternator power wire runs from the alternator to the solenoid. This wire should be at least a 8 gauge quality wire. I get mine from a stereo shop that uses good multi-strand wire. Is this the setup you have?

 

Hey ****** thanks for the reply, I haven't had a problem with the starter, but yea I'm running a autozone ground wire to the starter and the stock power wire from the original 4.3L to the alternator. I'm actually getting a .2 volt drop or so from the alternator to the battery, I didn't read into it much but I think you're right, I need to replace that power wire for sure and also the one running to the starter. I was more focused on the fuel pump itself, but I'm not thinking that's the problem now because it seems to be a progressive drain loss because like I said, the tach (auto meter) will die first. Then I'm starting to look for the shoulder. BTW it will run all day long regular traffic, just that gridlock stuff doesn't work.

 

This makes me think that it is heat related.

Andrew

 

In my Isuzu, I have two pumps and two hotwire kits, plus a digital fuel pressure gauge. I kick on the second pump occasionally to keep it loose, but I've never had an issue with my setup. The S10 bucket is huge compared to a 4th gen Fbody, so I absolutely threw a second pump in there. I think your issue is wiring to the pump, but the bucket is plenty large enough to add a second if you feel ambitious.

 

That's what I thought too because the engine is really stuffed in there, and I live in TX and this summer was no joke. I already cut the hood up and put in vents and I wrapped the headers & it didn't really help, it runs cooler but I still have that traffic time bomb thing. I'm going to replace a bunch of wires this weekend, possibly run a hotwire kit next weekend, that doesn't work I'm getting a second battery, that doesn't work I'm getting a huge alternator.

 

 

Also, I know about the under hood temps in the Isuzu. Not an issue for the fuel pump. I do see my voltage drop as everything warms up, but the pumps don't sneeze with the hot wire kits.

 

OK thanks Melonwheels, I just cut a hole in my housing and put the sock through there when I put the Walbro in, I still run the stock 5/16 lines or whatever size they are? I like the big wires coming out of that plug, that is part of the hotwire kit? That oval plug looks like mine, do you remember what kit you used?

 

I still use a bucket, just cut it open. The wires coming out of the electrical bulkhead are for the second pump, they are not part of a kit. PsychoSid bought some teflon insulated wire on eBay and I used some for my second pump. The primary pump wiring and level sender still go through the oval bulkhead, which is stock for the truck. I have a hotwire kit for each of the pumps, relays mounted nearby at the bed support. Racetronix supposedly sells all that stuff except the electrical bulkhead, which I bought from Jegs. I'm surprised I don't have a picture of the 8AN 90 bulkhead, but it;s in the hole there in the pictures.

 

Cool I have had the bed off like 5X by now so not a big deal I guess, I'm going to order that racetronix kit. I also have a 02 Camaro M6 super clean that I'm going to be boosting this winter probably run dual pumps in that because I have a E85 station a block away from my house. I will be referring back to those pics. Thanks guys.

 

Sounds like you're in the right direction, but be warned, the Fbody bucket is much shorter so you don't have all that space to get the discharges together. On my Fbody, I had to run two 6AN bulkheads and combine outside the tank. PsychoSid managed to do two pumps in a bucket with a single 8AN bulkhead, his would be the one to copy for that car. Good luck!