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

[Bachert24]

Be careful on what FPR you order. Several wrong ones will fit, but only a few have the proper pressure and i can not remember the number of the proper one.

I’m told 217-3299 is the correct one

 

[BeXtreme]

Has O2 sensors on the manifolds still. P00D9 is coming up as FPR or Fuel pump as likely culprit.

P009D is a fuel pressure relief valve code... an L29 does not have one of those. You will never get such a code for a FPR in an L29. That is a code that will show up on Gen 3 LS motors.

The code you have is P00D9... which is an ambient air temp sensor circuit code.

Again... test, don't assume or you will spend more time and money on it and just be frustrated if it doesn't fix the actual problem. You have several circuit low fails... so I would start testing for voltage and good ground on the O2 sensors and the IAT sensor. Once those are fixed, you need to make sure you have at least 9-12" of exhaust pipe after the O2 sensors for it to not throw a fault and run rich in closed loop mode.

Test the fuel pressure with the vacuum line connected and running. It should be ~52-54psi. Then disconnect the vacuum line, it should jump up to ~58PSI. If it does that, you don't have a pump or FPR problem. I would also replace the fuel filter just as a matter of course. You have no idea when it was changed last and it is a normal maintenance item that could be contributing to these issues.

 

[Scottm]

How bad is the gas? I would siphon it all out.

 

[Carlaisle]

Scottm's comment about the gas is a good one. How old is it? If you don't know, you could save yourself a lot of headaches by using it to start a bonfire and replacing with new.

I'm not sure about the FPR you indicated, but FP10021 is definitely correct. That engine is more sensitive to the fuel pressure than most. Test the pressure. Key on, engine off should be 56-62 and hold steady. It won't hold steady forever, but if you can easily see it leaking down you have something that needs fixed. If it is lower, you need to figure out why and fix it. If it is within spec, the problem is elsewhere. That 1" piece of hose that runs the FPR needs replaced at your mileage. There is no manufacturer provided specification for running fuel pressure.

Unless your oil pressure sending unit has failed you are better off keeping it. Access sucks with the engine in the vehicle and nothing you can buy new is of equal quality to what the manufacturer installed on the assembly line. If you do replace it, be sure you buy or rent the appropriate special socket. It is not optional for the job.

 

[Spareparts]

I’m told 217-3299 is the correct one

Many are listed as fitting, but most are the wrong pressure. I would not order a single one unless the pressure is listed in the description so you know it's the proper one.
I ordered 3 or 4 before i found the proper one.

 

[Bachert24]

Scottm's comment about the gas is a good one. How old is it? If you don't know, you could save yourself a lot of headaches by using it to start a bonfire and replacing with new.

I'm not sure about the FPR you indicated, but FP10021 is definitely correct. That engine is more sensitive to the fuel pressure than most. Test the pressure. Key on, engine off should be 56-62 and hold steady. It won't hold steady forever, but if you can easily see it leaking down you have something that needs fixed. If it is lower, you need to figure out why and fix it. If it is within spec, the problem is elsewhere. That 1" piece of hose that runs the FPR needs replaced at your mileage. There is no manufacturer provided specification for running fuel pressure.

Unless your oil pressure sending unit has failed you are better off keeping it. Access sucks with the engine in the vehicle and nothing you can buy new is of equal quality to what the manufacturer installed on the assembly line. If you do replace it, be sure you buy or rent the appropriate special socket. It is not optional for the job.

Thank you for this info I’ll do some testing this weekend! Fuel is 9 months old but only about 2-3 gallons I topped it off with a fresh 2 gallons. Everything I’ve read online states in a properly sealed fuel system there is no amount of degradation in the fuel itself.

 

[Carlaisle]

Gasoline degrades over time. The alcohol they add to gas now absorbs water from the atmosphere which does little to enhance the combustion process. 9 months would not typically be long enough to cause noticeable problems but, as previously stated, I am not convinced the tires on that truck sank that far into the dirt in 9 months. 2 gallons of lighter fluid + 2 gallons of gas won't get most internal combustion engines running very well.

 

[Bachert24]

Gasoline degrades over time. The alcohol they add to gas now absorbs water from the atmosphere which does little to enhance the combustion process. 9 months would not typically be long enough to cause noticeable problems but, as previously stated, I am not convinced the tires on that truck sank that far into the dirt in 9 months. 2 gallons of lighter fluid + 2 gallons of gas won't get most internal combustion engines running very well.

Fair point but tires are flat and dry rotted lol

 

[Bachert24]

Many are listed as fitting, but most are the wrong pressure. I would not order a single one unless the pressure is listed in the description so you know it's the proper one.
I ordered 3 or 4 before i found the proper one.

Scottm's comment about the gas is a good one. How old is it? If you don't know, you could save yourself a lot of headaches by using it to start a bonfire and replacing with new.

I'm not sure about the FPR you indicated, but FP10021 is definitely correct. That engine is more sensitive to the fuel pressure than most. Test the pressure. Key on, engine off should be 56-62 and hold steady. It won't hold steady forever, but if you can easily see it leaking down you have something that needs fixed. If it is lower, you need to figure out why and fix it. If it is within spec, the problem is elsewhere. That 1" piece of hose that runs the FPR needs replaced at your mileage. There is no manufacturer provided specification for running fuel pressure.

Unless your oil pressure sending unit has failed you are better off keeping it. Access sucks with the engine in the vehicle and nothing you can buy new is of equal quality to what the manufacturer installed on the assembly line. If you do replace it, be sure you buy or rent the appropriate special socket. It is not optional for the job.

Ok finally tested fuel pressure key on I’m getting 54 and it doesn’t hold long gets down to 48 within 30 seconds

 

[BeXtreme]

Ok finally tested fuel pressure key on I’m getting 54 and it doesn’t hold long gets down to 48 within 30 seconds

Well, that verifies you have a fuel pressure issue.. but doesn't narrow down why. You could have a bad check valve in the pump, leaking injectors, or a bad regulator. If you block off the return line and the fuel pressure builds above 60 PSI and doesn't bleed down anymore, you will have narrowed it down to the FPR.

If you block the return line and pressure still doesn't build and still bleeds down, then you need to check power and ground wires at the pump to make sure they are solid. If they are, then you have a bad pump.

If the pump build up above 60, but still bleeds down, you should check fuel volume by seeing how fast it fills a container of a known size. If volume is good, then you will need to pull the manifold and fuel rail out with the injectors still connected and see if you can see the injectors actually leak. If they aren't leaking, then it is a bad pump.