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Discussion Starter #1
i have an 03 silverado with the 5.3 engine. what should the fuel pressure be on it? i had an issue where all 4 02 sensors threw a code for low voltage when i kicked her down. its almost like i'm not getting the fuel pressure i should be getting.
 

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Discussion Starter #6
thanks guys...going to check it here after while. hopefully it will be a problem with the regulator and not the pump.
 

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Discussion Starter #7
well i just checked it. at idle with the regulator hooked up i had 45psi. when i would unplug the regulator it would go up to about 55-58 range. does this seem normal?
 

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Discussion Starter #8
i left it hooked up and ran the hose out onto the hood so i could see it going down the road. just cruising it was at 45 then when i would kick it down it would go up to 55.
 

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Discussion Starter #12
wonder which would be best to start with then? the regulator or the pump? is there some where i can hook up my gauge before the regulator to see what the pump is putting out?
 

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There is a test you can do for the regulator. Remove the vertical boot coming up off the top of the regulator while the engine is running. If gas drips out then the regulator is definitely bad. I don't know if passing the test assures you that the regulator is working correctly though.
 

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Discussion Starter #15
have you guys heard much about the connection being bad at the pump. a friend of mine had this happen after he had already replaced the pump. i'm going to check mine out here shortly. would be nice to just be a bad connection dropping the voltage for the pump.
 

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Discussion Starter #17
well i went ahead and ordered a fuel pump off of ebay. its suppose to come with a new connector as well. hopefully have it by wednesday and get it put on that night. i'll post up how it goes. my check engine light came on again when i was pulling my rhino around on the trailer. again it was for all 4 02 sensors low voltage. i'd think that if it was the pump it would have lost all pressure by now. it'll be my luck that i will change out the pump and it end up being the regulator or something else.
 

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Since you're going to guess and throw parts at it anyway...Order a regulator, it's less work to replace and cheaper. Wait to put the pump in until after the regulator doesn't fix it.

I don't think that you're looking in the right place at all. I think it would give you a lean code, not a low voltage code, if you were running lean. Anyway, there are other reasons it could be lean, like a leak in the intake past the MAF (likely a throttle body gasket or something) or a leaky vacuum line.

Take that with a grain of salt...I suck at this.
 

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Discussion Starter #20
so you guys dont think my fuel pressure being at 45 at idle is a problem then? how much vac should i have at idle?
 
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