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+--- Thread: running rough and black smoke (/showthread.php?tid=8828)
running rough and black smoke - tdawg - 04-05-2023
I have a cm870 that started running rough and pouring black smoke. Lots of fuel in oil. The harder you get on the fuel the worse it gets. I thought maybe a sticking injector so did a bubble test and no bubbles on front or back. Can a bad actuator make it run this rough? The egr is blocked. Turbo seems to be working fine.
RE: running rough and black smoke - Rawze - 04-05-2023
cm870...
turbo air actuator controller going bad or turbo arm hanging up are the most likely culprits.
RE: running rough and black smoke - tdawg - 04-05-2023
(04-05-2023 )Rawze Wrote: cm870...
turbo air actuator controller going bad or turbo arm hanging up are the most likely culprits.
If I floor it the turbo jumps up to 30 but it shakes and skips like an injector is stuck open. Skips and smokes at idle.
RE: running rough and black smoke - Running rough - 04-05-2023
check for cracked pickup tubes in fuel tanks, and maybe for fuel suction leaks on fuel system, could also be bad timing or metering actuaters
RE: running rough and black smoke - trucklogger2 - 04-05-2023
pop off the valve cover... inspect with engine off and running
RE: running rough and black smoke - tdawg - 04-05-2023
(04-05-2023 )Running rough Wrote: check for cracked pickup tubes in fuel tanks, and maybe for fuel suction leaks on fuel system, could also be bad timing or metering actuaters
I'm wondering if actuators can make it run that bad?
RE: running rough and black smoke - tdawg - 04-11-2023
Changed all the actuators and nothing changed. ran the truck and watched everything without the valve cover on but don't see anything wrong. Exhaust gass temp. is pegged at 15 at cold start up. Changed the sensor and same thing. Gauge test showed the gauge is fine. No codes
RE: running rough and black smoke - trucklogger2 - 04-11-2023
(04-05-2023 )tdawg Wrote:(04-05-2023 )Running rough Wrote: check for cracked pickup tubes in fuel tanks, and maybe for fuel suction leaks on fuel system, could also be bad timing or metering actuaters
I'm wondering if actuators can make it run that bad?
To test them you would switch their position front to back after cylinder cutout test front three back three and seeing if problem cylinders follow actuators. Also look at harness for fuel on contacts.
But where is fuel in oil coming from? you'll end up washing cylinders if you don't pinpoint that problem. I thought maybe the source could be under the valve cover via an injector, so you would see fuel mixing in oil there.
Also the smoke from either a dead cylinder or exhaust valve or turbo/and or actuator or fuel actuator
So many things eh
sorry if I missed something
oh yeah check the value for the atmospheric pressure sensor-should match local barometer press
RE: running rough and black smoke - Rawze - 04-11-2023
you sure it does not have a hole burned thru a piston?.