I have a 91 F-350 with a N/A 7.3 IDI. How do you know if the IP is timed correctly? Or if I have bad injectors? The truck recently has started running rough and smoking. I have checked for blow by, thinking maybe I had some rings going but didn't notice anything out of the ordinary. The truck seems to make decent power for what it is, but will miss going down the road at times, and blow whitish/gray smoke, and every now and again blueish/gray smoke. Doesn't seem to burn a terrible amount of oil either. Almost seems like the motor is loading up or something................any help would be appreciated, and I can give more info if possible. Also as far as I know the IP has not been turned up. And I do have a cracked passenger side exhaust manifold. Would that have any affect.

 

Sounds more like injector troubles. How many miles?

 

sounds like its picking up air from fuel water sep. or a crackes in fuel line.... start with a fuel water seperator without a bowl on the bottom.. a one piece filter... like a baldwin BF-1222..... thats what I run.. start cheep and work your way through the system.....