91 ford f150 wont start

[ninerman]

the engine is a 300, i have new plugs, cap, rotor, wires, and sensors. it turns over but wont start on the first try. after 4 or 5 times it will start, but runs very rough. may be misfiring, but not sure. there is a valve on top of the air induction unit that i think may be bad, i cleaned it and it seemed to help a little. any ideas?

 

[ninerman]

the IAC is what i tool apart and cleaned btw

 

[Skandocious]

How old is the fuel filter? Sounds like perhaps you're not getting enough fuel out to the cylinders.

Welcome to the site!

 

[ninerman]

thank you.... this is actually a question for my dad, and he isnt giving me great descriptions, so i apologize if everything isnt as clear as it should be... also, i asked him about the fuel filter, he says its a year or two old....

 

[95F350XL]

If its missing you can pull wires of the plug while its running, not all the way off, just enough to see what ones make it run worse or do nothing. When you have the cylinder pin pointed, id ck compression, if its good, id say your injector is bad. If you unplug all wires and the motor runs worse with each one you pull then there is other probs to y its running rough. Does it matter what gas tank you run from? Front or rear if you have dual tanks. As Chris(skan) said might not have enough fuel pressure.