[mike 96 ws6]

I threw a rod in my 2003 S10 ZR2 4.3 and bought a 2005 4.3 out of a Silverado to replace it. The motor came complete with the intake, throttle body, injectors, ect. so thats how I installed it other than a few items that were different (exhaust manifols, valve covers, PCV valve, oil pressure sending unit, ect.)
But the new motor was hard to start and low on power and setting P0171 & P0174 (lean condition - both banks).
A fuel pressure test showed only 20 PSI (KOEO). Specs are 55-62. And an instant drop to 0 PSI when the ignition was shut off. So I figure either I have an injector (s) leaking or a fuel pressure regulator leaking. So I swapped out the Fuel meter assembly with all 6 injectors attached from my old motor, and installed a new fuel pressure regulator. But when I install the injectors into the manifold, some of them won't lock into seated position and are loose enough to pull out easily. What do I need to do to lock these injectors in place?
Thanks,
Mike

[LATECH]

you are correct to have checked the injectors for a leak, however they wont set a lean code if leaking. It should be running carbon black rich as all that fuel leaking would cause as it runs through the engine.
It sounds like a bad pump. Check valve not holding and unable to make specified pressure- classic pump symptom.
Those injectors will stay put in the hole,dont sweat that.
If it were mine I would buy the upgrade injectors, ditch the poppet setup.The poppet ones are pretty troublesome.Even with good fuel pressure they plague the engine with lean codes and random misfire codes, POS

[mike 96 ws6]

I'd like to get a good set of injectors. Where do you suggest ordering from? And I was hoping I wouldn't have to buy a pump yet but I guess It's better to get it done too, along with ~$5000 of parts I've bought since I bought the truck in December. I was thinking about a Walbro 255 lph pump. I've run them in my LT1 f-bodys with good results. Or is there a better option?
Thanks latech!

[LATECH]

Its just a daily driver, dont go overboard. I have had great success with the spectra fuel systems parts, and advanced auto parts, believe it or not. They are actually pretty good.
I have had 1 fail in 5 years, and actually it didnt quit, the line popped off of the pump feed line because it wasnt crimped at the factory.The pump still was OK. Had to pull the tank out again to change it.
We do tons of pumps and lines here in the rust belt.
Look around at spectrapremium.com pretty good stuff.

[LATECH]

Spectra for the fuel pum
Sorenson for the spider. Be sure to replace it with the kind in this photo, with wires that go to individual injectors, not with a "poppet" style that is in it.

[mike 96 ws6]

Advanced list 2 Spectra pumps for my truck, both include sender, float, reservoir, and cost #268 & $355. I'd rather find just the pump and strainer for less $ but I'm not having much luck.

[mike 96 ws6]

Originally Posted by latech

Spectra for the fuel pum
Sorenson for the spider. Be sure to replace it with the kind in this photo, with wires that go to individual injectors, not with a "poppet" style that is in it.

The spider that is in it has individual wires going to each injector.

[LATECH]

Thats a KEEPER. your good to go.

When you get it done, put some Seafoam or Chevron fuel injector cleaner in it to clean up any crud that may be left in the fuel system or engine.

[mike 96 ws6]

Originally Posted by latech

Thats a KEEPER. your good to go.

Excellent. I can save some money and start eating again.

[LATECH]

Originally Posted by mike 96 ws6

Advanced list 2 Spectra pumps for my truck, both include sender, float, reservoir, and cost #268 & $355. I'd rather find just the pump and strainer for less $ but I'm not having much luck.

268 sounds about right for retail, from what I have seen. The quality is there, so its good stuff. They will price match if you find it cheaper, also if you talk to the store manager and tell him you ight buy it from Pep boys or autozone , he will give you a better price so he doesnt lose the sale.
better to make a few bucks than none at all...right?

[LATECH]

Mmmmmmm.....eating...

[mike 96 ws6]

Problem solved. I now get 65lbs fuel pressure (KOEO) and 55lbs (engine running at idle).
I agree with you latech. I would think the injectors leaking, or a leak from the fuel meter would flood the motor with gas. And the regulator produces more pressure at lower vaccum so a hole in the diaphram or leaking o-ring should also flood the motor. But those are the only parts I replaced and fuel pressure is good, it cranks right up, power is back and no codes.
But there may be an explanation. Basically, the only difference I saw between the 2005 parts vs 2003 parts was that the connection for the fuel return line on top of the 2005 fuel meter was plugged with a factory plug. The 2005 Silverado uses a returnless type fuel system - More information here. But other than that plug the fuel meters looked identical, and the Silverado meter also has a regulator (which seems redundant seeing as how that vehicle has an in-tank regulator.
I don't know. I'm just happy my motor is running good!!!

[T-bucket23]

Originally Posted by mike 96 ws6

Problem solved. I now get 65lbs fuel pressure (KOEO) and 55lbs (engine running at idle).
I agree with you latech. I would think the injectors leaking, or a leak from the fuel meter would flood the motor with gas. And the regulator produces more pressure at lower vaccum so a hole in the diaphram or leaking o-ring should also flood the motor. But those are the only parts I replaced and fuel pressure is good, it cranks right up, power is back and no codes.
But there may be an explanation. Basically, the only difference I saw between the 2005 parts vs 2003 parts was that the connection for the fuel return line on top of the 2005 fuel meter was plugged with a factory plug. The 2005 Silverado uses a returnless type fuel system - More information here. But other than that plug the fuel meters looked identical, and the Silverado meter also has a regulator (which seems redundant seeing as how that vehicle has an in-tank regulator.
I don't know. I'm just happy my motor is running good!!!

Low fuel pressure can set a lean code, leaking injectors will not