2004 F550 6.0 diesel 220k miles intermittent no start, highway buck/jerk/black smoke

[dfarryessir]

so far Ive replaced; injectors 1,3,4,7, HPOP and solenoid, fuel pump and new regulator kit, HPO sensor, EP sensor, EGR cooler and oil cooler

buck/jerk/black smoke on highway goes away when BARO sensor is unplugged. replaced. no change.

intermittent no start( hot, cold, warm-- no bias). starts when exhaust pressure sensor is unplugged or with a shot of ether. installed relay to "unplug" EP sensor only when cranking--this worked great for 2 days and now i have same intermittent no start and overboost(35 psi on hiway) this blew a charge air hose. highway Buck/jerk/black smoke goes away completely when brand new BARO sensor is unplugged. im about to change my VGT actuator. anybody have any idea whats next when this doesn't work?

[jonesy_11950]

What are the codes? Has it been scanned?

[dfarryessir]

only codes were open EGR valve (probably caused by me unplugging it) and havnt had codes ran since overboost issue.

[lawman349]

My bet is FICM. Can you have the voltage checked?

[dannyboy950]

in all your doings did you clean out the tube when you replaced the ebp sensor.

[Deer Creek]

Originally Posted by lawman349

My bet is FICM. Can you have the voltage checked?

I second that! I was going through the same thing and it turned out to be my FICM . . . . . . . . . . . . . . .

[dfarryessir]

Looks like the VGT actuator was the culprit. No more intermittent no starts, no over boost. Will post what happens when I find baro sensor and plug it back in-- think it may run more efficiently wit it. Thanks

[dfarryessir]

The truck definitely has more power with Baro sensor plugged in and still no buck jerk or black smoke. However, intermittent no start has returned (with or without baro sensor). I suspected voltage drop
To ficm during cranking-- so I cleaned terminals and checked--10.2 volts when cranking. Ebp tube is clean. Just a tiny shot of ether is all it takes to get it going. Any other ideas?
Thanks