Return style fuel system on a 2005

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Can a return style fuel system from a 2002 Tahoe work on a 2005 model that comes with returnless from the factory? Pretend you have every single part needed to do it: injectors, rails, lines, fuel pump, etc. and I'm guessing tuning the PCM. Can it be done?
 

stutaeng

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Yes.

I think in this or another forum (maybe performancetrucks.net?) it was discussed that you could swap to a return style setup, the whole system.

For high performance applications, the return style is supposed to be better, I can't remember why at the moment. You'd also regain the fuel in-line filter if that matters...
 
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AuroraGirl

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Yes.

I think in this or another forum (maybe performancetrucks.net?) it was discussed that you could swap to a return style setup, the whole system.

For high performance applications, the return style is supposed to be better, I can't remember why at the moment. You'd also regain the fuel in-line filter if that matters...
fuel circulation When youre at high demand or full throttle in a suped up engine, the fuel returning will be minimal, the reason for not having return is for cost and for reducing tank temperatures because warm fuel doesnt return to it, but the pump/filter life is gonna be more dependent on things.
 

Tonimus

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Yes.

I think in this or another forum (maybe performancetrucks.net?) it was discussed that you could swap to a return style setup, the whole system.

For high performance applications, the return style is supposed to be better, I can't remember why at the moment. You'd also regain the fuel in-line filter if that matters...
Another reason high performance applications use it is to prevent large air pockets. My nitrous system runs a return style regulator so I don't have to worry about leaning out when the system hits.
 

stutaeng

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Return style is I think easier to diagnose. You can simply temporarily plug or cap the return hose and check for maximum pump pressure delivery, and see if maybe the fuel pump check valve is releasing back pressure on the feed line. I'm not sure that you can do that on a returnless system. I don't think you can actually.
 

stutaeng

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GM switched to it just to save cost I'm sure. And from all I've read about both return and returnless systems, return systems are better.
Yes, most likely. Google also says the returnless is better for emissions. Probably less fuel vapor loss or something?

So are you thinking of converting to a return fuel system on your truck? It would be interesting to see how easy/difficult to swap and how long that takes...
 

Marky Dissod

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... wanted to retain the return system but still use the '05 PCM and the drive by wire TB
Not sure, but I THINK there is such a thing as a P59 pcm that can support mech cable throttle & return fuel system.
Should be blatantly obvious that there are earlier P01 pcms that support mech cable throttle & return fuel system.
 
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I found the answer I was looking for: there's a "switch" in the PCM tune that allows you to choose return or returnless fuel system. Can't remember exactly what it says. Constant duty cycle option and something else for the other one. That's it
 

AuroraGirl

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I found the answer I was looking for: there's a "switch" in the PCM tune that allows you to choose return or returnless fuel system. Can't remember exactly what it says. Constant duty cycle option and something else for the other one. That's it
I see what you mean by looking back at it, but it wasnt clear from your beginning posts, only after the "i have 02 tahoe fuel system and want to use it with my 05 z71 pcm"

The 03 trucks have the same pcm and return fuel system. So definitely possible.
 

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