2000 GMC 1500 with an unusual starting problem

I have a 2000 GMC 1500 Sierra truck with a 5.3 V8, and it has an unusual starting problem. It always starts great in the morning when the engine is cold and the vehicle has set over night. If I drive it for 15 or more miles enough so that the engine is up to operating temperate and let it set for a just few minutes it starts without a problem, but if it set for hour or more it is hard to start. It also idles badly and there is smell of gas, and my gas mileage has dropped.

[quote=tpurer]I have a 2000 GMC 1500 Sierra truck with a 5.3 V8, and it has an unusual starting problem. It always starts great in the morning when the engine is cold and the vehicle has set over night. If I drive it for 15 or more miles enough so that the engine is up to operating temperate and let it set for a just few minutes it starts without a problem, but if it set for hour or more it is hard to start. It also idles badly and there is smell of gas, and my gas mileage has dropped. I just replaced the sparkplugs, but this did not help.

Most likely, your fuel pressure regulator is bad and leaking fuel. The fuel evaporates over night and that is why it starts easy in the morning. After a hour, the engine is flooded and runs rough (you also smell gas). Not enough gas leaks in a few minutes so it starts fine then.

//2000CAYukon

I have a similar problem. I have changed spark plugs, fuel pump assembly, and fuel pressure regulator but still have the same problem. I also notice some surging at steady speads. I am going to try replacing the injectors next. I would appeciate any other sugestions.

I have a similar problem. I have changed spark plugs, fuel pump assembly, and fuel pressure regulator but still have the same problem. I also notice some surging at steady speads. I am going to try replacing the injectors next. I would appeciate any other sugestions.

ours was doing the same thing and replaced the mass air flow and it fixed the problem