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Discussion Starter · #1 ·
Near the spare tire on the left side is a small box with the GM p/n 20831727. Called parts dept. and they said it was a "Fuel System Module". They did not know what it did. Called the service dept. they said they thought it had something to do with the fuel pump. Does anybody know what this does?
 

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ccharlie said:
Near the spare tire on the left side is a small box with the GM p/n 20831727. Called parts dept. and the said it was a "Fuel System Module". They did not know what it did. Called the service dept. they said they thought it had something to do with the fuel pump. Does anybody know what this does? :mad: :mad:
The fuel system module as I understand helps regulate the PSI of fuel by controlling the high pressure fuel pump. DI engines can run upward of 2000psi (the 2.0 SIDI Turbo was 2600psi @ WOT). I think ours are in the 1000-1500psi, but have not checked it personally
 

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Previous posts said that the fuel pump is in the engine or engine area. How could this work if that is true? I have a noisy motor and some suspect that the fuel pump is the culprit among other things.
 

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ccharlie said:
Previous posts said that the fuel pump is in the engine or engine area. How could this work if that is true? I have a noisy motor and some suspect that the fuel pump is the culprit among other things.
There are TWO fuel pumps.

One is on the timing chain (mechanical) and one is in the fuel tank (electrical). The mechanical one is the one that ups the PSI to what the engine needs.
 

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ccharlie said:
Previous posts said that the fuel pump is in the engine or engine area. How could this work if that is true? I have a noisy motor and some suspect that the fuel pump is the culprit among other things.
As mentioned below......You have a "cam" driven fuel pump in the engine, and a tank fuel pump to send fuel to the mechanical. I was told the pump in the tank is high pressure as well, being its what makes the "returnless" fuel system possible. Its suppose to provide a continous pressure to the engine bay, what the pressure is I have no idea...

Your noisy motor is what is known as Direct Injection....It sounds similar to a diesel engine in idle, that is becuase the technology in direct injection and diesel injection is VERY similar...in fact nearly the same. Alot of that sound you hear is the valve train (2 cams, 16 valves 1 timing chain (chains are noisey vs belts but reliable), the DI injectors (which are actually more like a high pressure soleniod valve...they are the sound most people here squirt, squirt, squirt) and then the cam rail fuel pump
 

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bballr4567 said:
There are TWO fuel pumps.

One is on the timing chain (mechanical) and one is in the fuel tank (electrical). The mechanical one is the one that ups the PSI to what the engine needs.
im sorry but im having difficulty understanding all the mechanical part. I am a bit confused. So if the mechanical is ups to what the engine needs, how about the electric fuel pump? Please advice. Thanks
 
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