5.3 slow to start when at operating temp.

Discussion in 'GM Powertrain' started by Route66dan, Jan 31, 2010.

  1. Route66dan

    Route66dan New Member

    I have a 2000 Silverado with 75,000 miles on it. No trouble at all for 10 years with normal maintenance. Now it starts fine when cold, but after driven and warmed to operating temps, it takes 3 or 4 attempts to get it to start. After it starts, it runs fine. The fuel pressure at the manifold is 50 psi and it displays no trouble codes when scanned. I've never changed the fuel filter, but don't know if that would be a factor since it appears I'm getting enough pressure. Could this problem be a temp sensor, or throttle position sensor? Any thoughts would be appreciated.
  2. J_chevyman

    J_chevyman Rockstar


    That weird that your getting enough pressure but it wont start til a few clicks. Mine does that same thing but my pressure is like at 24, and i need to repalce my fuel pump for sure. Hopefully that will help me with the pressure. Hopefully some here has a answer
  3. Reviction

    Reviction New Member


    My 2000 with the 5.3 does about the same thing. It always starts fine cold, but after its warmed up it will just keep cranking and never start (ok, it might start after some cranking 10% of the time). But, it ALWAYS starts immediately the 2nd time I try it.
  4. Route66dan

    Route66dan New Member

    It was the FUEL PRESSURE REGULATOR. There were two different styles, mine was the earlier of the two. You can look on Rockauto to see photos of them. One way to tell if yours is bad is to pull off the vacuum line to it and see if there is any fuel in (the line). If so, the diaphragm in the regulator is toast and allowing fuel to pass thru and out the vac line. A new Delco Fuel pressure regulator costs about $60-$75. Not cheap, but easy to replace and fixed my problem. Back to starting quick on first try. Hope this helps. Someone else clued me in on this fix. Might check the fuel filter if it hasn't been replaced. :happy:

Share This Page

Newest Gallery Photos