RepairPal is your advocate for car care advice and guidance

Q: after sitting over nightwill not start on first try but starts on second try on 2001 GMC Sierra 1500

seems like it is not getting gas on the first try,once it starts then I turn it off it stars fine it only starts hard after sitting over 8 hours it has anew fuel filter
Get a Repair Estimate
Guaranteed by certified locations nationwide. Learn more
RepairPal estimates are guaranteed at over 1,700 quality certified locations nationwide. Learn more
sounds like a fuel pump that has lost its prime. have the pressure checked first thing in the moring to verify.

Should be on the fuel rail on the side with return line to fuel pump. I'm not sure what adapters you'd need for that year set-up. parts store may have basic pressure guage kits with the adapters and what they work on. Might want to pick up a Haynes or chiltons manual for a little better guidance and for the specifications (both running and shut-off after sitting-generally 10 min.). Also the pressure regulator should have a vacuum line to it , If that line has fuel in it when you pull it off , generally that's a sign of failure. HOPEFULLY if I'm giving you any mis-information , somebody will kick in with a reply stating that! Good luck.
Install a fuel pressure gauge to the service port on the fuel rail, turn ignition to run in order to prime the fuel system. Watch the fuel pressure gauge after you have successfully primed the fuel system, wait for about 5-8 minutes and watch the gauge. If it drops more than 5psi in a couple of minutes or if it drops to zero, then the fuel pump module needs to be replaced. Has a bad pressure check ball that is allowing the prime to be lost.
Didn't find what you were looking for?