compression test

[turbovair]

Recently my truck has begun to:
1. start a little harder in the morning(rough)
2.lose power (generally)
3. smoke (black) excessively during even part throttle application
The truck has 126,000 with original fuel injectors,uses no coolant and otherwise runs OK.

My thinking is to have the compression and timing checked...then(if OK):
1.replace fuel injectors
2.cat converter
3. diesel pump
(One at a time until problem solved)
Any thoughts?

[AndyL]

Do you have plenty of boost while blowing black smoke?

[turbovair]

Yes, I forgot to mention that. About 4-6 PSI at partial throttle. Boost seems to be OK. About 5-8 at full throttle...but too much smoke to stay there long without fogging the streets.

[turbovair]

Oh, also my computed fuel economy at last fillup(two days ago) was slightly over 16(with 4:10 ratio)I routinely usually run 15-17 MPG.So fuel economy really hasnt changed much.

[tom.mcinerney]

Sounds like good plan.
Keep in mind possible bad tank of fuel (maybe try additive//check filter for crud)....and a tired FSD.
I think you replaced your ig sw; did clean conns+gnds too?