1996 k1500 5.7l 150000 miles ecm1 fuse blows

[Tiny Tony]

I was going to say,... there's a lot of pink wires that have potential to ground out...

At least you didn't run out and change your fuel pump! I'm joking!

LOLOLOL No but they are highly suspect. I bought this truck new and I've put a few pumps on it. I keep a pressure gauge on standby.

 

[Silverado1994]

LOLOLOL No but they are highly suspect. I bought this truck new and I've put a few pumps on it. I keep a pressure gauge on standby.

Yessir.....it doesn't take but just a few pounds short of the spec to ensure a no start every time. Funny how that is. Most other fuel injection systems can run on a few pounds less than the regular pressure but not this system.

Sorry 'bout the foul up earlier. lol

 

[Silverado1994]

I was going to say,... there's a lot of pink wires that have potential to ground out...

At least you didn't run out and change your fuel pump! I'm joking!

It's all good. I've learned over the years to be a fairly humble guy.

You must be registered for see images attach

 

[Tiny Tony]

Ok well as expected a self inflicted issue! It's taken a long time to sort out but, I have increased my diagnostics skill, or lack there of. I went over the wiring harness with a fine tooth comb and pulled the fuse box which looked very good and couldn't get anything to reveal itself. I fired the parts cannon and put a genuine coil on it as to maybe an internal issue and, I put in a auto reset breaker in place of the fuse and drove. I went for prolly 350 miles over three weeks or so and no issues. Still not finding the smoking gun was thinking I was good. Then one morning I started it up to go to work and backed up about three feet and it shut off. I thought here we go hoping this would stay happening so i left the key on and the breaker was clicking away. I went over and unplugged the coil and the clicking breaker continued. I puled the plug on the ignition module and the clicking continued. i pulled the air intake tubing off and then pulled the large injector plug and wouldn't you now it the breaker quit clicking. So after a few more days i swapped the old cfi injector back in and found on the new injector, with the wires that follow the fuel tubes, I had indeed pinched one of the wires between the fuel tube and the housing bracket. As I said self inflicted!!!

 

[Tiny Tony]

I also forgot before i unplugged the injector I unplugged every plug on the ecm because i was suspicious of that and the breaker continued to click on and off. The only thing left was the crank sensor and I didn't make it to that one. i'll post up a pic tonight of the culprit.

 

[Erik the Awful]

Makes sense. Your fuel injectors get key-on power and the ECM switches the ground to control them. Good find.

 

[alpinecrick]

Yes, good find on the injector issue.

When you say “Amazon” fuel injector spider, is this a AC Delco or Delphi unit?

Also, what usually kills quality fuel pumps ( AC Delco or Delphi) is not changing the fuel filter often ( every 15k). Even a mildly plugged fuel filter significantly shortens the lifespan of a pump. A quality fuel pump with regular filter changes may last as long as the motor……

And, although no way to prove it, regular fuel filter changes, and using quality gas (Top Tier fuel), seems to go a long ways towards extending the lifespan of the factory SCFI injectors. I have four Gen 1 Vortecs V8’s, ranging from 170k to 270k, and although one has the Delphi MPFI replacement, it turns out the original was fine, and so are the other three original SCFI spiders.