My truck is a 2010 5.3L Silverado. I have recently been having some hard starting issues with my truck. I have replaced the battery (with an optima), tested the starter and alternator and both tested fine. From what little I have been able to research about my issue. It appears that I am having a fuel pressure problem. On the start up it almost doesn't want to fire up, but once it has started it runs perfectly fine. The issue arises when the truck has either sat overnight or for a long period of time, such as all day at work. I have found that if I turn the key on and allow the fuel pump to "prime" it starts alot easier, but still with some hesitation. I suspect it to be a fuel pressure regulator problem, however from what I have seen the 2010 Silverado's don't have fuel pressure regulators. So I am at a loss for what the issue is or how to go about fixing it. I am trying to avoid taking it to the dealer which comes with expense. Any help or ideas would be greatly appreciated. I fear that I may have to replace the fuel pump, but I don't think the pump is bad as the truck runs great once it gets started. Thanks in advanced!!

 

if your symptom is a long crank time and it starts normally after priming the fuel system by multiple key cycles; it is a fuel pump check valve fault.

This can be confirmed by installing a fuel pressure gauge and watching for a pressure drop after the engine is shut off.

The fix is to either replace the fuel pump as the check valve is part of the pump assembly or install an external check valve in the fuel line close to the tank.

 

Is the truck off of warranty? You don't say the mileage.

 

I appreciate the responses, the truck is not under warranty any longer as it has roughly 75,000 miles. unless the fuel pump is part of the 100,000 mile powertrain warranty which I doubt. I have plugged in a diagnostic computer to check if codes had been thrown and none have been. So I'm guessing I am going to have to get a new fuel pump.

 

On my 99 several years ago, I put a check valve in the fuel line near the tank and that solved the problem. Start right away every time.