When first starting the engine it's a little slow to fire up maybe 3-4 seconds then if you try to take off it bake fires through the intake. Once it gets up to about 125- 150 it starts to run a lot better. After that it has a slight hesitation and seems like it doesn't have good power once rpms build up it has good power. I put new plugs,wires,rotor,cap temp sensor, I took a fuel pressure reading at the fuel filter it read 15 psi checked vacuum line and fixed anything that looked dry rotted and such. I got this truck in a trade and the guy who had it before me made a mess.It has headers there's wires not plugged in to anything air pump missing and I don't know what else is missing. One more thing when timing is set on 2 with ecm unplugged my timing mark is way to the left not even in degree indicator marks like it's to far advanced.I know timing is suppose to be on 0 but I didn't think 2 degree's would make a lot of difference. Any suggestions please