Another 454 Vortec Build Thread - Documenting, Q&A, Help

[BeXtreme]

You could also use a c-clamp with a hard piece of wood or plastic on the round side to protect the hose as well

 

[Bachert24]

https://www.harborfreight.com/4-pie...jKtFenWA5tL2pKzmSG9NPVV2B8XFYKeoaAopnEALw_wcB
or
https://www.harborfreight.com/line-...KgmqJcLMcmGGnru0k1EWwdFp5o0GXu_QaAucQEALw_wcB
or I've used needle nose vise grips with another piece of rubber hose over the line to protect it from damage.

Beautiful thank you sir I have a large c clamp that might do the trick I’ll try this tomorrow and report back. As far as the fuel rail goes it was 54psi and dropped 1 psi every 10 seconds I believe

 

[Scottm]

How's the compression? No sense worrying about injectors if it's not healthy.

 

[Bachert24]

How's the compression? No sense worrying about injectors if it's not healthy.

I haven’t tested it but 99% certain it’s good since I drove it like 10 miles, but it did run like crap and backfire occasionally so would be good to test but I don’t have the tools for that. Also this thing is draining batteries anyone know best way to look for battery drain? I don’t even know where to start there’s so much electrical in this truck it’s just overwhelming to even know where to start.

 

[Bachert24]

I’m going to test the fuel pressure tomorrow with a jump since my battery is dead dead and if it tests ok then I will have to buy tools to test compression.

 

[Moofus02]

I haven’t tested it but 99% certain it’s good since I drove it like 10 miles, but it did run like crap and backfire occasionally so would be good to test but I don’t have the tools for that. Also this thing is draining batteries anyone know best way to look for battery drain? I don’t even know where to start there’s so much electrical in this truck it’s just overwhelming to even know where to start.

I like a seat belt buzzer. Put it between the positive and the battery cable. If there is a drain it will buzz. With everything shut off hook it up. If it buzzes pull fuses until you find the circuit that is causing the issue. Leave that fuse out and replace the rest one at a time. If it buzzes when you put in another fuse note what circuit and leave that one out until you get fuses in without buzz. Then track the offending circuits until you find the drain

 

[BeXtreme]

I’m going to test the fuel pressure tomorrow with a jump since my battery is dead dead and if it tests ok then I will have to buy tools to test compression.

You can rent tools for free from Autozone or Oreillys. That includes compression tester, multimeter, fuel pressure tester, etc..

For battery drain, disconnect the battery cable from the positive terminal and connect a multimeter between the positive terminal and the battery cable. Select amperage(A) on the multimeter and see if you show a number with the key off and the door closed. If it shows ANY number above 0, you have a drain. Make sure you don't see any lights on also, including the one under the hood.

To narrow down where the drain is coming from, start pulling fuses one at a time until you see the number on the multimeter drop. Once you find a circuit with a drain, pull out the wiring schematics(available for download on this forum) and see what items are on the specific fuse. Start disconnecting individual components on that circuit until the number drops on the multimeter(now you have found the culprit). You might have more than one circuit with a drain. Just work it to the end on each circuit independently.

 

[Bachert24]

You will just end up chasing your tail and spend tons of money to potentially solve nothing like that. There have been lots of good advise on how to simply troubleshoot your problem and you seem to completely ignore it and instead laser focus on something that everyone is telling you IS NOT the problem.

There is no fuel pressure sensor on your truck. The Fuel TANK pressure sensor is only used for EVAP system testing when the truck is first turned on and is not used in your application... regardless of whether there is a sensor installed in your fuel sending unit. The fuel pump itself is the same for almost all GM trucks/SUV's from ~96-2003.

Put a fuel pressure sensor on the rail and then test the pressure(I know you already did this). Record the pressure key on/ engine off. Turn key off and record how fast the pressure drops(PSI/second). Then do what spareparts said and pinch off the return line. Record the key on/ engine off pressure. Turn key off and record how fast the pressure drops(PSI/second). If your pressure with the return line pinched off is over 60psi and it doesn't bleed off very fast after you pinch the return line closed, your entire problem is the FPR. Full stop.

Ok key on test at rail is 54 psi and drops about 1 psi every 10 seconds. I’m not sure which line is the return line so I tried both. 1 line psi hits 54 and slowly drops, other line psi hits 58 then slowly drops. Possibly 1 psi every 30 seconds.

 

[Spareparts]

Either way the pressure when testing a pinched off return line should be over 70PSI. If it bleeds off that much with the return line pinched, you mostly likely have bad injectors or less likely but possible to have a bad line in the tank at the pump or a bad check valve at the pump or just a weak worn out pump.
Too bad your not closer to North Idaho, i have a used good pump in the shed i would give you.

 

[Spareparts]

After thinking about this a minute, I don't think you had the lines pinched off totally.
If you had a pressure line pinched off, you would get 0 pressure reading. If you pinch the other off, you should get way more pressure.