Slow Starts

[dsc73]

I have a 2001 Yukon XL 4x4 with a 5.3 and 95,000 miles. When the motor is cold it starts right up. After the motor is warmed up it turns over and over before it fires? No check engine lights or messages? I have done all maintenance per the owner’s manual, other than this vehicle runs great. Any help would be appreciated.

[AKvsAR]

Had the same thing happen on my 99 Sierra.

 

Fuel Pressure Regulator.

 

http://vibratesoftware.com/images/Vortec%205300.jpg

 

If you look between the coil over packs, in the center is a grey connector plug. The FPR is the circular device right above that.

 

Pull the vacuum hose off the top, and if fuel comes out, it's bad.