Hi everyone. New here. I have a 2006 F-250 Lariat 6.0L and as far as i know there are no mods(bought with 109k) other than I removed EGR. I change oil every 5k and fuel filters 10k. I was towing my camper home and truck started blowing black smoke. It doesn't seem to have a loss of power but does idle rough. I figured i had a sticky injector so I added a bottle of injector cleaner to just over a half tank of fuel(~13G). I drove the last 50 miles, which used over a quarter tank, and smoke persisted. I borrowed a Snap On scanner and checked for codes but only the EGR codes were present. I ran injector buzz test and that checked good. Turned off each injector individually and each one made engine run rougher. FICM voltage is 47-47.5. ICP is 580-600psi at idle and increases with throttle. Ran contribution test and cylinders seem to randomly drop below zero with no misfires reported.

Long story short I am at a loss. My thinking is still a stuck injector but dont want to throw hard earned cash at dumpster fire.

Thanks in advance for any suggestions.

 

A sticky injector? Look at your ipr duty cycle. It can give you an idea if the truck is working harder to maintain adequate fuel pressure.

 

The only thing i can find on the scanner is the ICP Duty Cycle which stays right at 20% at idle and up to around 40% at 2500 RPM.

 

Wanted to update this post. After talking to more people and running every test I could i decided that there was and injector letting too much fuel in. I bit the bullet and ordered a full set of injectors. I found the pictured injector in cylinder #1. As you can see the lower O-Ring is blown out allowing fuel to dump into cylinder.