P2149 code-next step?

[SBilinski]

I have a stock 2006 3500 4x4 with 111k miles. I have been getting a p2149 code. I disconnected the wires to injectors. I checked resistance across the injectors and the valve cover gasket from plug to injector wire. All tested at .3 ohm. What would the next step be?
Thanks

 

[DonFitzwater]

Have you tested the other wiring between the PCM and engine? Any other trouble codes? Any running problems or missing?

 

[SBilinski]

No other codes. When light comes on, it shuts down 3 cylinders, other than that, no running issues. I was going to check resistance on wire harness from valve cover gasket, but was not sure where the other end was. Looks like it goes from valve cover down side of block into a big bundle with looms going out multiple directions. It didn't look like there were the same colored wires down at PCM as there was at valve cover

 

[AllianceDiesel]

I have seen injectors fail and once cool a little go back to inspec. When I get home Ill get you the diagnostics

 

[Bob Wagner]

Problem is usually in the valve cover gasket that holds the wires that run to the injectors. If the computer senses a short or open in one of the 3 (1-3 is group A, 4-6 is group B I think) it shuts of that bank of injectors, and you are left on 3 cylinders. shut it off, resets code, fires up and goes like nothing is wrong. then if conditions are right, things move or wiggle just so, happens again.


Never personally dealt with it but I have heard of several people with similar or exact same symptoms, that was the fix.

 

[AllianceDiesel]

Set Condition: A misfire detected at cylinders 4,5, or 6 or any combination of cylinders 4,5, or 6.

Possible Causes
OTHER DTC’S
HIGH SIDE DRIVER CIRCUIT OPEN
LOW SIDE DRIVER CIRCUIT OPEN
HIGH SIDE DRIVER SHORTED TO LOW SIDE DRIVER
HIGH SIDE DRIVERS SHORTED LOW
LOW SIDE DRIVER CIRCUIT SHORTED OTHER LOW SIDE DRIVER CIRCUIT
LOW SIDE DRIVERS SHORTED LOW HIGH SIDE DRIVER SHORTED TO VOLTAGE
LOW SIDE DRIVER SHORTED TO VOLTAGE
LOW SIDE DRIVER CIRCUIT SHORTED IN INJECTOR HARNESS
INJECTOR INJECTOR
HARNESS '
ECM
INTERMITTENT CONDITION


Do you have any combination of DTC’s P0204, P0205, or P0206?
Yes >> Repair other DTC’s first.
No >> Go To 2

2. HIGH SIDE DRIVER CIRCUIT OPEN

Turn the ignition off. Disconnect the ECM harness connectors. Disconnect the Injector 4-6 harness connector.
NOTE: Check connectors - Clean/repair as necessary. Measure the resistance of the injector high side driver circuit between the Bank 2 high side driver circuit in the ECM harness connector and the high side driver circuit in the injector harness connectors for cylinders 4-6.

Is the resistance less than 10 Ohms?
Yes >> Go To 3
No >> Repair the open high side driver circuit from ECM harness connector to the Injector harness connector.

3. LOW SIDE DRIVER CIRCUIT OPEN

Measure the resistance of the #4,#5, and #6 injector low side driver circuits between the ECM harness connector and the injector harness connectors.

Is the resistance less than 10 Ohms?
Yes >> Go To 4
No >> Repair the open low side driver circuit.

4. HIGH SIDE DRIVER SHORTED TO LOW SIDE DRIVER

Measure the resistance between the Bank 2 high side driver circuit at the ECM harness connector and the low side driver circuit for injectors 4-6 at the ECM harness connector.

Is the resistance more than 100k Ohms?
Yes >> Go To 5
No >> Repair the High side circuit shorted to the low side circuit.

5. HIGH SIDE DRIVERS SHORTED LOW

Measure the resistance of the injector harness connector high side driver circuits to battery negative for injectors 4-6.

Is the resistance more than 100k Ohms?
Yes >> Go To 6
No >> Repair the High side driver shorted low in the harness.

6. LOW SIDE DRIVERS SHORTED LOW

Measure the resistance of the injector harness connector Low side driver circuits to battery negative for injectors 4-6.

Is the resistance more than 100k Ohms?
Yes >> Go To 7
No >> Repair the Low side driver shorted low in the harness.

7. HIGH SIDE DRIVER SHORTED TO VOLTAGE

Turn Ingition on, engine off. Measure the voltage between the high side driver circuit in the engine harness and battery negative.

Is the voltage less than 1 volt?
Yes >> Go To 8
No >> Repair the high side driver shorted to voltage.

8. LOW SIDE DRIVER SHORTED TO VOLTAGE

Measure the voltage between the low side driver circuit in the engine harness and battery negative for cylinders 4-6.

Is the voltage less than 1 volt?
Yes >> Go To 9
No >> Repair the low side driver shorted to voltage.

9. LOW SIDE DRIVER CIRCUIT SHORTED OTHER LOW SIDE DRIVER CIRCUIT

Measure the resistance of each of the Bank 2 low side driver circuit to all other Bank 2 low side driver circuits at the ECM harness connector.

Is the resistance greater than 100k ohms?
Yes >> Go To 10
No >> Repair Low side driver circuit shorted to other Low side driver circuit.

10. LOW SIDE DRIVER CIRCUIT SHORTED IN INJECTOR HARNESS

Reconnect the disconnected injector harness connector. Measure the resistance of each of the Bank 2 low side driver circuit to all other Bank 2 low side driver circuit at the ECM harness connector.

Is the resistance greater than 100k ohms?
Yes >> Go To 11
No >> Replace the injector harness.

11. INJECTOR CIRCUITS SHORTED INSIDE ENGINE

Measure the resistance of each injector from the through head connector.

Is the resistance greater than zero and less than 1 ohm?
Yes >> Go To 12
No >> Go To 14

12. INJECTOR Disconnect the pigtail nuts from injectors 4-6.

NOTE: Check connectors - Clean/repair as necessary. Measure the resistance between the solenoid posts of each injector.

Is the resistance less than 1 ohm and greater than 0 ohms?
Yes >> Go To 13
No >> Replace the fuel injector or injectors

 

[Bob4x4]

Problem is usually in the valve cover gasket that holds the wires that run to the injectors. If the computer senses a short or open in one of the 3 (1-3 is group A, 4-6 is group B I think) it shuts of that bank of injectors, and you are left on 3 cylinders. shut it off, resets code, fires up and goes like nothing is wrong. then if conditions are right, things move or wiggle just so, happens again.


Never personally dealt with it but I have heard of several people with similar or exact same symptoms, that was the fix.

That has been my experience in the shop,about 95% of the time

 

[cerberusiam]

VC gasket or even a solenoid that is heating up and shorting out. The VC gasket is easier to start with.

 

[SBilinski]

Thank you all for the great info. I got a v/c gasket on the way from Geno's. I will follow the diagnostic procedure further if the gasket doesn't cure the issue