Fuel pickup at startup problems

I have a 2002 GMC Yukon 2wd 5.3 Liter. It has approximately 80,000. Lately, I have had what seems like fuel pick-up problems at start up only. From new until recently, the car would easily turn on simply by turning the key without having to step on the gas. Now I have too turn the key at least twice before it will turn on. Even when I press on the gas pedal, it still takes a few seconds for it to start. I've changed the spark plugs, had the fuel system, including the fuel injectors cleaned at a service shop. The vehicle runs fine, it's only this particular issue at start up, that's got me puzzled.

does it only have trouble starting when cold, or both hot and cold, if it does it when hot, it sounds like vapor lock, has it been hot or humid in your area. im no expert but this may help.

Response

It usually does it when it's cold and/or been sitting for while. As far as humidity is concerned, we live out in Arizona where it's pretty dry. As mentioned earlier, I turn the ignition the first time for a second or two and no start. Let it go and immediately turn the ignition on again and it starts up. I have tried several times to see what would happen if I kept the ignition turned for several seconds during an initial startup attempt. All that happens is it keeps turning (I'm assuming the starter) but the engine does not turn on. One more thing, it doesnt seem that the starter has lost any of its power either.

Sounds like an early warning sign that the fuel pump is on it's way out. After sitting for awhile it 'loses it's prime' so to speak, the pressure is allowed to leak back into the tank and then must be built up again after sitting awhile. It will only get worse and eventually will need a new fuel pump.

Not an expert but most likely what the problem is.

Also check the fuel pressure regulator. They are famous for starting problems like yours. It sits on the drivers side near the fuel rail. There is small black hose that attaches to it. Pull it off and smell it. If you smelll gas, then the regulator is bad.

I agree with above. On our Sheriff Tahoes, the most that goes out are the fuel pumps and throw in a fuel regulator on top of that here and there. A buddy has a shop and he contracts for Fish and Game rigs and he says about the only problem with the Tahoes/Suburbans are the fuel pumps. He said to throw in a can of Techron once in a while. Been doing that since I bought mine and have no problems yet....knock on steel!

We get 265,000 miles on our Tahoes, and you know how cops drive. It can be done with good maintenance. I hope to get 300,000 out of mine before something bad goes wrong.

Aaron

When you say fuel rail I believe that you are not reffering to a throttle body, (if i'm using the right terminology) mine looks like a normal old fashioned carb that has the injectors mounted inside.

Do you still think the regulator could be the culprit? (that is if mine indeed has one)

I used to have a newer Tahoe that had the annoying hum of the pump whenever the key was on but this one I have never noticed sounds coming from the tank like what I have heard coming from my newer Tahoe.