2010 Silverado Loosing Fuel Pressure

lineman · February 8, 2011

I have a 2010 silverado with the 5.3. A few months ago it acted like it was starving for fuel when i started it. Took it to dealer and they said that it was putting out 49% and factory spec was 51% so they put a new fuel pump in. A few days later i was doing the same thing, so took it back and they said they couldnt find anything wrong so i left it overnite. When i went to get it the next day they said they it still wouldnt do it for them. So the mechanic went out with me to start it and it did it. He then told me that after i turn on the key that i need to wait a few seconds to get power to the fuel module so that it can get fuel to the motor. Is this true or was he feeding me a line, he said they just started doing it on the 2010. So after that i started it and it was fine i kinda felt dumb, but after the truck sits for several hours it does the same thing even if i wait a few seconds before i start it. Has anyone else had this issue? Or does any mechanic have any advice? Its loosing fuel pressure somewhere.

olibert · February 10, 2011

I don't know the newer Vortec engines but it might be an issue on the other end of the fuel supply. So it might be caused by a dripping injector or bad fuel pressure regulator.

So probably a good starting point to tackle it is to get one of the cheaper fuel pressure gauges from Harbor Freight and to check how the fuel pressure behaves after parking the car.

8.1HD/ALLISON · February 10, 2011

+1 on the fuel pressure guage. Need to check fuel pressure and see how fast it drops.

LeoS41280 · February 10, 2011

I don't know the newer Vortec engines but it might be an issue on the other end of the fuel supply. So it might be caused by a dripping injector or bad fuel pressure regulator.

So probably a good starting point to tackle it is to get one of the cheaper fuel pressure gauges from Harbor Freight and to check how the fuel pressure behaves after parking the car.