1987 GMC Suburban 1/2 ton 4x4 N/A 6.2. A couple days ago my truck started having an issue. I had always started perfectly, however now it starts up normal and right away runs for about 3 seconds and then races and dies. Then after lots of more cranking, normal glow plug cycles, and white smoke it slowly comes to life. This only happens on the first start of the day. I do not think it is a glow plug issues since it starts normally at first and they have nothing to do with the idel racings. Lack of fuel or fuel presure? Air in the sytsem. What might make a normal start turn into a raceing rpm, die and hard start?? I have posted on here a few times looking for help and have always been please with everyones idea and knowledge. Thanks in aadvance efor your help and or insight

An air leak in your fuel lines. There's enough fuel left in the IP to start the motor, but it's leaked down in the fuel lines prior to it leaving you with no fuel until you crank for a while and the lift pump supplies more to the IP.

Either that, or faulty lift pump. Could be both.

Thank you for the advice, an air leak in a fuel line is what I was figuring as well. Is there a particular line or lines I should look at first or can this problem result equally from any location? Thank you again for your input.

Well, I would look at the lift pump and fuel filter first, being in the engine compartment they get the most vibration and heat.