Maybe its time for someone to stepup and make one of these for the NBS and NNBS crowd.
Or is there one already? and I just have not found it yet.

Fuel pump Hotwire kit


Found the Correct kit

Racetronix Fuelpump rewire and relay kit, PNP!

 

Looks like a simple relay? Run 10-12 gauge to the relay from the battery and then from the relay to the pump. Use the stock fuel pump wire to trigger the relay and you have a hotwire kit.

 

I'm getting about 10-11 mpg, The truck only has 41k miles on it and no my check engine light isn't on.

Something else isn't right. I topped my truck out today and my Speedo was only registering 80-82. Any thoughts?

 

Well, If you are getting awful mileage, there is too much fuel going to each cylinder. Right? Sounds like the fuel system is working just fine..... (I'm slightly joking of course)

You just need to figure out what is commanding the extra fuel.

Bad/dirty MAF, clogged cats, bad O2s? Loss of power. None of these things should be going bad, but its possible.

 

Im gonna go out and ask the dumb question here but you dont have huge *** rims and not havnt adjusted the speedo do ya?

If your hand calculating your mileage and have huge *** rims there is your issue, if your going off the data center they are almost always off either high or low doesnt matter. Thats also the only reason other than regearing without adjusting the computer i believe that would cause it to do that unless something more is goin on i dont know about which is highly possible .

If its not the wheels and tires or gears id say what Coban said definatly check the MAF sensor if your using an oiled filter it definatly could have fouled the sensors cause it happened to my camaro and damn thing ran like **** with no power and sluggish till you hit 70 then it was like someone kicked it in the *** and it took off. If not that i have no idea haha just tryin to help.

Have yo checked your rail pressure, wouldnt low pressure also cause it to be underpowered and sluggish.

 

speaking of fuel pressure, when tank is half full it's response is great, but when tank is full response is not so bad but not good and frustrating at times, specially when climate is very warm..
checked the fuel pressure and found a noticeable difference!!, think 40+ when full and 50/55+ avg or 60+ as max when half full...

I'm curious!, is this how it's(gmt900) designed...is it tunable? or what the heck?

 

The MAF is fine and I wouldn't think the Cats or O2s would be bad being the truck only has about 41k miles on it. I guess it wouldn't hurt to check em anyway.

The truck still has the stock Wheels and Tires. I still have the stock Air Filter as well. I checked it the other day and it was fine.

I haven't gotten around to checking the Fuel Pressure but I guess that would be the next step. I'm gonna check the O2s as well.

 

Nothing you have told me is pointing me toward an obvious answer but I will tell you that the fuel pump is covered by the 5yr/100k powertrain warranty and the cats fall under the 8yr/80k emissions warranty.

Your speed limiter shouldn't kick in until 100mph. What mods do you have?

 

As far as I know it's completely stock. I just bought it on the 27th.

I checked the O2s, they were a lil black, and I ran the truck for a minute without the O2s and it smelt pretty bad. Do you think the Cats are bad?

I called the dealer where I bought it and they told me to bring it in on Monday. I'm pretty sure everything will be covered under warranty.

 

Another question are you getting any codes or check engine light? I didnt see where you said you had and i thought you said you hadnt but check the engine for vacuum leakes, even brand new it can happen but not normal at all but **** happens.

Just one more thing to eliminate ya know, you can either use starter fluid and spray at the intake flanges or where ever you think there could be a vacuum leak or you could have it smoke checked.

If you were having a vacuum leak youd have a check engine light i believe, it worth a try to clean the 02's with ELECTRIC PARTS CLEANER nothing else and also just for ***** clean the maf sensors anyway. You dont want to go tossin 60 something bucks per 02 just to see they arent the issue.

again possibly way off here