My friend has a 2003 Chevy Silverado 3500 with the LB7 Duramax in it. It has a ton of upgrades done to it and we needed more fuel, added upgrade and sputtering

Jeremy Lindeman

Asked by Oct 21, 2012 at 04:38 PM about the 2003 Chevrolet Silverado 3500 4 Dr LS Extended Cab LB DRW

Question type: Car Customization

We added a Raptor 150 fuel pump to the truck along with the stock pump. We made sure that all the lines were in check and
everything turned out fine. But when we started the truck and tried to put his DSP5 switch in his extreme setting, and put the
throttle about half way down, the truck started cutting in and out. So, we tried a different setting. His fuel econ mode, and it cut
out in it too. Every setting we tried it started cutting in and out. It would still drive, but you hardly had any power. It also hazed
at light throttle. The only way you could get good performance out of it was if you turned the key on and off to let the pump
push more fuel to the engine and then start it. That would only last for a few seconds though. I guessed it was a bad pump, am I

3 Answers

John Saffrahn

The pump can't surpass the injectors capabilities. If enough modifications have been done then the computer needs to be flashed for the extra air so it can compensate with the fuel and if that doesn't help then you may need higher pressure injectors because the ones you have aren't handling the higher compression ratio, which isn't likely but still possible. Take it to a performance shop to have it dyno tuned.

1 out of 1 people think this is helpful.
Best Answer
Keith Egstad

i'll prolly be wrong but you put a petrol pump into a diesel. i think the pump cant take the viscosity of diesel fuel. the only reason i think that, is cause if you put diesel in a petrol engine it clogs up the fuel filter

John Saffrahn

It's a different pump he is referring to bud, he is talking about the high pressure pump.

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