Over the last year or so my truck has slowly became progressively harder to start when warm. Not that it is terrible problem yet, she always starts; but I would like to fix it.

I usually don't like to run the starter motor much more than 5 seconds at a whack (That is what my Dad preached me into believing as I was growing up). Sometimes it takes about halfway into the second attempt for her to start. A year ago it was usually about 1 or 2 seconds into the first attempt. She actually starts a bit easier when she is cold these days.

The batteries are good, and so is the starter (it turns over plenty fast). The air and fuel filters are fairly new. Nothing has been done to the engine (Timing, fuel system settings, etc) since the problem has slowly began to develop. Fuel pressure is the same (it has always been just a bit lower than what they say it should be, about 25-30 psi going down the road). I have tried no throttle and a little throttle while starting, which seems to work about the same. The truck runs just fine, has had no change in power, and gets about the same milage it always has. All the gauges read about the same.

Any suggestions on what I might look at?

 

Before you start it try pumping the primer button on the lift pump until you hear fuel passing though the overflow valve.
If it starts right up you have leak somewhere in the supply/return system that's sucking air.
Most times suction leaks don't leak fuel, just looking won't help.
Best way to find a leak is to pressurize the fuel tank to 10 psi max then go hunting.
Air blow gun wrapped in a rag works for pressurizing but then it takes two people, one to hunt the other to pressurize.

 

Thanks Bill, I will check that out.

 

Bill is bang on (as always).. That simple test will help you troubleshoot very quickly..