my 2001 chevy silverado pickup 5.3 liter is having trouble starting--cold or hot. fuel pressure is OK. does this motor have a cold start valve on it like the older fuel injected models?

yes it is called an EGR valve

Hmmm something called a fuel pressure regulator. Dont let the name fool you fuel pressure can still be fine but if that little bugger goes out it makes the truck hard to start hot or cold. Trust me i had same problem and changing it out is an easy do it yorselfer 20 mins.

Fuel Pressure regulator location is on right side fuel rail in the middle with a small vaccume line on it.