98 S10 ZR2 Starting ?

[movin2stereo]

I have a 98 S10 ZR2 4x4 with the 4.3 Vortec engine(throttle body injection).Most of the time when I hit the key,the truck fires right up with no problems(cold or warmed up)and sometimes I hit the key and it has to turn over for a second or two or three before it fires up(cold or warmed up).I would like to know what the problem is?This truck has over a 100,000 on it and has had a new engine put in it since.The new engine has like 2,000 on it now.This problem was also present before the new engine.Help!!!!!!!!!!!!!!!!!!!

[Jeremy-WI]

pay attention when you turn your key to the on position, do you hear the fuel pump kick on everytime when you start it. It might help to let the key set in the on position for a second before turning it to start

[movin2stereo]

Yes the pump kicks on.I've left the pump build pressure before and it didn't help.

[JOEROC]

Try a new fuel filter, air filter might help to.

[movin2stereo]

I have a cool air intake on it,so I don't think it's the air filter.But I never changed the fuel filter.