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Stock 2012 Cummins BILLOWS black smoke

22K views 25 replies 10 participants last post by  sepukacheekray 
#1 ·
I recently purchased a 2012 ram 2500 4x4 ST 6.7l cummins from auto auction. i got it cheap, but it billows black smoke when you accelerate. and not just a little. we're talking massive clouds here, enough to blind drivers behind you if you really get on it. at idle, it will puff barely visible clouds of black smoke. at idle when accelerator is first depressed, it bogs down for just a second and then takes off, as if its choking on too much fuel. i buy and sell trucks for a living, and this much smoke makes the truck unsalable. i am no diesel machanic, and what little i know i learned from poking around trucks or forums.

I began my diagnostics by cracking open the exhaust pipe between the cat and dpf to see if they'd been gutted. they are both intact. No check engine light currently. so i button her up and drive her for a few days to see if it'll throw codes.

a day later, it throws codes for cylinder 3 injector timing, EGR stuck and EGR cooler bypass dead. Checked the EGR and cooler bypass with my snap on MODUS ultra scanner. 0 communication with the egr bypass cooler, EGR out of performance. Slap on reman EGR, used EGR cooler bypass and a reman injector in cylinder 3. egr now functions as does bypass cooler. road test, and it still blows just as much black smoke out the back as before. the injector in cylinder 3 was reman as well, so I'm assuming the dealer who had it before me tried to fix it up before dumping it in auction. no check engine light has come back on yet.

I don't know if this truck has a tune on it, but when i got it, it didn't have a tuner or any sign that one had been there.

Some things that i have noticed:
1. at idle the egr cooler bypass valve will switch from open and then closed about every two seconds.
2. in park at idle, revving the engine through the rpm range will show roughly a 10% discrepancy between the desired and actual fuel pressures, the actual being lower.
3. i pulled the breather box off the filter to see if it'd smoke less when it had more air to breath, and that cut down on the smoke a bit

I am at a complete loss here. if someone could direct me on how to proceed to get a good diagnosis of this truck i'd be greatly appreciative. half the diesel folks in town that i talk to say you do need to program the injectors to the pcm, and the other half say it's not necessary. i have another cummins of the same model on my lot i can compare readings to or swap parts from, it runs perfect.

awaiting your help.
 
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#2 ·
Seems that remain injectors are never a good buy. As for the smoke sounds like it could be a stuck turbo. Shouldn't poor that much smoke, possible the old owner tuned it, then stated having issues with the turbo and sold it.
 
#5 ·
So i took the truck down the road and measured the VGT desired percent with the actual, it ran between 87%-37% under hard acceleration, and the boost peaked out at 22.8psi. no option on my scantool to see the wastegate, unless i just don't know what the fancy abbreviation for it is.
 
#6 ·
So many variables with a used truck from an auction with no knowledge of the history...

Does it look like the EGR and exhaust have been recently wrenched on?

Perhaps the previous owner reinstalled all the emissions equipment back on prior to the sale?

That means, who knows what program is in the ECM?

Plus the boost at 22.8PSI peak is way too low. The truck must be quite doggy with that low of boost.


1st I would want to flash the trucks' ECM to a known stock/factory program to eliminate that variable.

Then figure out why the boost is so low. Boost leak, VGT Turbo stepper motor issues, etc.


Good luck, I hope you are able to resolve the issue..
 
#9 ·
Sounds to me like it has to have a delete tune in it but the emissions was reinstalled. Hence why its not throwing codes for emissions. Ive personally never seen a dpf allow an engine to billow black smoke even with it almpst completely plugged (I deal with them a lot with John Deere), so there could be an issue inside the dpf as well. I personally would remove the entire dpf and inspect it with a fine tooth comb or take it somewhere for cleaning and inspection and as mentioned before have the dealer flash a factory tune back into it. Then have them put the engine through a manual regen and that will tell the tale as to what issues it might still have.
 
#11 ·
Ok, so made some progress last night. upon listening to the truck idle and rev outside the vehicle, it sounds like it has some fuel knock. the truck has a light rough idle, so i ran an injector kill test on it. cylinders 1-5 made the truck idle noticeably worse when they were dead, however, when i commanded cylinder 6 off, the truck's rough idle barely got any worse. the change was hardly noticeable. gonna swap cyl 6 injector with another cylinder to see if the symptom follows the injector.

I have a smoke machine, so after that i'll look for a boost leak, but i'm thinking the dpf load from the soot may be keeping it from building proper boost.

another thing i noticed when feeling of the injector fuel lines, number 3, the one i replaced already seems like it pulses just a little bit harder than the others. not by much though.

monday morning i'll take it to the stealership and have it reflashed and the latest software put on it.

i changed the oil when i first got it, and now it's a little overfull, guess that #6 injector is pissing diesel into the pan.
 
#18 ·
Ok, so made some progress last night. upon listening to the truck idle and rev outside the vehicle, it sounds like it has some fuel knock. the truck has a light rough idle, so i ran an injector kill test on it. cylinders 1-5 made the truck idle noticeably worse when they were dead, however, when i commanded cylinder 6 off, the truck's rough idle barely got any worse. the change was hardly noticeable. gonna swap cyl 6 injector with another cylinder to see if the symptom follows the injector.

I have a smoke machine, so after that i'll look for a boost leak, but i'm thinking the dpf load from the soot may be keeping it from building proper boost.

another thing i noticed when feeling of the injector fuel lines, number 3, the one i replaced already seems like it pulses just a little bit harder than the others. not by much though.

monday morning i'll take it to the stealership and have it reflashed and the latest software put on it.

i changed the oil when i first got it, and now it's a little overfull, guess that #6 injector is pissing diesel into the pan.

Took it to the dealership. turns out the pcm was under recall, so they flashed it and updated the software for free. they also did a recall fix on the fuel heater. still smokes like crazy, no change...


While getting the ECM flashed to stock to eliminate that variable was an excellent step, I'm surprised you are still driving the truck
if fuel is going into the engine oil.
I do not recommend running the engine until the injector issue is resolved.

At a minimum, swap in a new #6 injector.

Better yet would be to pull all 6 injectors, send them off to get tested.
Run a compression test while you are waiting.
 
#15 ·
I know some guys who would like to have that truck---as is........LOL
 
#20 ·
P0203-FUEL INJECTOR 3 CIRCUIT/OPEN

Theory of Operation

The Powertrain Control Module (PCM) actuates the solenoid in the Fuel Injector causing the needle valve to rise and fuel flows through the spray holes in the nozzle tip into the combustion chamber. The PCM has a common internal driver circuit to all three Fuel Injectors on each bank. If any injector circuit on a given bank has a failure, a DTC will be set for all three Fuel Injectors on that bank. Fuel Injectors 1,2,3 are grouped together on bank 1. Fuel Injectors 4,5,6 are grouped together on bank 2. The MIL lamp will light immediately after the diagnostic runs and fails. During this time the customer may experience engine surge or stumble. The MIL lamp will turn off once the diagnostic runs and passes in four consecutive drive cycles.

- When Monitored:
While the engine is running.

- Set Condition:
When the Fuel Injector current falls below a calibrated threshold.




Report this image



1. ACTIVE DTC
1. Ignition on, engine not running.
2. With the scan tool check for active DTCs.

Is the DTC active?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. See: Computers and Control Systems > Initial Inspection and Diagnostic Overview > Intermittent Condition Test.




2. CHECK EACH FUEL INJECTOR CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the PCM C1 harness connector.
3. Measure the resistance between the:
- (K11) Fuel Injector 1 High Side Driver circuit and the (K611) Fuel Injector 1 Low Side Driver circuit at the PCM C1 harness connector.
- (K12) Fuel Injector 2 High Side Driver circuit and the (K612) Fuel Injector 2 Low Side Driver circuit at the PCM C1 harness connector.
- (K13) Fuel Injector 3 High Side Driver circuit and the (K613) Fuel Injector 3 Low Side Driver circuit at the PCM C1 harness connector.

NOTE: Be sure to zero the Ohm meter prior to checking the Fuel Injector circuit. Resistance reading should be between 0-1 Ohm.

Is the resistance between 0-1 Ohm on all circuits?

Yes

- Go To 3

No

- Go To 8




3. CHECK EACH FUEL INJECTOR CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the:
- (K11) Fuel Injector 1 High Side Driver circuit at the PCM C1 harness connector.
- (K12) Fuel Injector 2 High Side Driver circuit at the PCM C1 harness connector.
- (K13) Fuel Injector 3 High Side Driver circuit at the PCM C1 harness connector.

NOTE: There should be no continuity between the circuit and ground.

Is the resistance less than 10k Ohms on any circuit?

Yes

- Go To 12

No

- Go To 4





4. CHECK EACH FUEL INJECTOR CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn Ignition on.
2. Measure the voltage on the:
- (K11) Fuel Injector 1 High Side Driver circuit at the PCM C1 harness connector.
- (K12) Fuel Injector 2 High Side Driver circuit at the PCM C1 harness connector.
- (K13) Fuel Injector 3 High Side Driver circuit at the PCM C1 harness connector.

NOTE: There should be no voltage present.

Is there voltage present on any circuit?

Yes

- Go To 6

No

- Go To 5

5. CHECK FOR THE DRIVER CIRCUITS SHORTED TOGETHER
1. Turn ignition off.
2. Disconnect all bank 1 Fuel Injector wires at the Fuel Injectors.
3. Measure the resistance between all bank 1 Driver circuits at the PCM C1 harness connector.

Is the resistance below 10k Ohms between any Driver circuits?

Yes

- Repair the Driver circuits that are shorted together.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Replace the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

6. CHECK THE HIGH SIDE DRIVER CIRCUIT FOR A SHORT TO VOLTAGE

NOTE: Perform the following tests on the Fuel Injector circuit which was faulty.

1. Turn the ignition off.
2. Disconnect Fuel Injector wires at the Fuel Injector.
3. Turn the ignition on.
4. Measure the voltage of the High Side Driver circuit at the PCM C1 harness connector.

Is there any voltage present?

Yes

- Repair the High Side Driver circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Go To 7

7. CHECK THE LOW SIDE DRIVER CIRCUIT FOR A SHORT TO VOLTAGE
1. Measure the voltage of the Low Side Driver circuit at the PCM C1 harness connector.

Is there any voltage present?

Yes

- Repair the Low Side Driver circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Test complete. Perform the INTERMITTENT CONDITION diagnostic procedure. See: Computers and Control Systems > Initial Inspection and Diagnostic Overview > Intermittent Condition Test.

8. CHECK THE VALVE COVER PASS THROUGH HARNESS CIRCUIT
View & Print Options




NOTE: Perform the following tests on the Fuel Injector circuit which was faulty.

1. Disconnect the Valve Cover Pass Through harness connector.
2. Measure the resistance between Low Side Driver circuit and the High Side Driver circuit at the Valve Cover Pass Through connector terminals.

NOTE: Be sure to zero the Ohm meter prior to checking the Fuel Injector circuit.

Is the resistance between 0-1 Ohm?

Yes

- Go To 9

No

- Go To 11

9. CHECK THE HIGH SIDE CIRCUITS IN ENGINE HARNESS
1. Measure the resistance of the High Side Driver circuit between the Valve Cover Pass Through harness connector and the PCM C1 harness connector.

NOTE: Be sure to zero the Ohm meter prior to checking the Fuel Injector circuit.

Is the resistance between 0-1 Ohm?

Yes

- Go To 10

No

- Repair the High Side Driver circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

10. CHECK THE LOW SIDE CIRCUITS IN ENGINE HARNESS
1. Measure the resistance of the Low Side Driver circuit between the Valve Cover Pass Through harness connector and the PCM C1 harness connector.

NOTE: Be sure to zero the Ohm meter prior to checking the Fuel Injector circuit.

Is the resistance between 0-1 Ohm?

Yes

- Test complete. Perform the INTERMITTENT CONDITION diagnostic procedure. See: Computers and Control Systems > Initial Inspection and Diagnostic Overview > Intermittent Condition Test

No

- Repair the Low Side Driver circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

11. CHECK THE FUEL INJECTORS
1. Disconnect all bank 1 Fuel Injector wires at the Fuel Injectors.
2. Measure the resistance across the terminals at the Fuel Injector.

NOTE: Be sure to zero the Ohm meter prior to checking the Fuel Injector circuit.

Is the resistance between 0-1 Ohm?

Yes

- Replace the Valve Cover Pass Through harness.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Replace the Fuel Injector.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

12. CHECK FOR THE DRIVER CIRCUITS SHORTED TOGETHER
1. Disconnect all bank 1 Fuel Injector wires at the Fuel Injectors.
2. Measure the resistance between all bank 1 Driver circuits at the PCM C1 harness connector.

Is the resistance below 10k Ohms between any circuits?

Yes

- Go To 13

No

- Go To 14

13. CHECK THE VALVE COVER PASS THROUGH HARNESS CIRCUITS
View & Print Options



1. Disconnect the Valve Cover Pass Through harness connector.
2. Measure the resistance between all bank 1 Driver circuits of the Valve Cover Pass Through connector terminals.

Is the resistance below 10k Ohms between any circuits?

Yes

- Replace the Valve Cover Pass Through harness.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Repair the short between the bank 1 Driver circuits in the engine harness.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

14. CHECK THE HIGH SIDE DRIVER CIRCUIT FOR A SHORT TO GROUND

NOTE: Perform the following tests on the Fuel Injector circuit which was faulty.

1. Disconnect the Valve Cover Pass Through harness connector.
2. Measure the resistance between ground and the High Side Driver circuit at the PCM C1 connector.

Is the resistance below 10k Ohms?

Yes

- Repair the short to ground in the High Side Driver circuit.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Go To 15

15. CHECK THE LOW SIDE DRIVER CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the Low Side Driver circuit at the PCM C1 connector.

Is the resistance below 10k Ohms?

Yes

- Repair the Low Side Driver circuit for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Go To 16

16. CHECK THE FUEL INJECTORS
1. Measure the resistance between ground and one of the Fuel Injector terminals.

Is the resistance below 10k Ohms?

Yes

- Replace the Fuel Injector.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. See: Computers and Control Systems > Diagnostic Trouble Code Tests and Associated Procedures > Powertrain Verification Test.

No

- Replace the Valve Cover Pass Through harness.
 
#22 ·
What i do not understand is the smoke. If there is a dpf it will take it all out unless it is cracked. It will just plug up. How is all that smoke getting through.


Sent from my iPhone using Tapatalk
 
#26 ·
PROGRESSSSSS!!!!! so i found out which pins to test on the harness. tested injector one high side on the pcm harness, had over 10k ohms resistance when it should have no continuity. injector 2 is the same, while injector 3 has no continuity like it should. moved onto voltage test. according to the paper, injector high side should be dead with the ignition on and the pcm harness disconnected. injector 3 high side was dead. injector one has battery voltage when turned on and injector 2 fluctuates from .2v to 3v whether the ignition is on or not. don't have the diagnostics for the last 3 injectors, but i'd suspect there's a short in those as well.

yay. now the fun part, finding the shorts or replacing the whole harness.
 
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