P0191 Code

[DavidStevenson]

I have a 04. 5 5. 9 with 15,600 miles on it and the MIL came on with P0191 CODE. What does this code mean and can I still tow my 10,000 lb trailer for a short 100 mile trip without any problems?

 

[JPereira]

Found the following on Dodge Diesel.org. There were several posts of others setting this code on a failed startup. Did not sound like a major issue. Try searching on wwww.dodge-diesel.org and read some of the posts.



Jeff



P0191-FUEL RAIL PRESSURE SENSOR PERFORMANCE

When Monitored:

At key on.

Set Condition:

The fuel pressure sensor reading at key on does not match the expected fuel pressure reading at key on

Possible Causes OTHER DTC'S PRESENT FUEL RAIL PRESSURE SENSOR FUEL SYSTEM TAMPERING INTERMITTENT CONDITION

Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

Diagnostic Test

1. OTHER DTC'S PRESENT



With the scan tool, read DTCs.

Are any DTC's present?

Yes

Repair other DTC's first.

Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)



No

Go To2





2. FUEL PRESSURE READING



Using the scan tool, monitor the actual fuel pressure reading while the key is on and engine is not running.

Is the actual fuel pressure reading greater than 870 psi?

Yes

Go To3



No

Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)





3. FUEL RAIL PRESSURE SENSOR



Visually inspect the fuel system components for signs of tampering, pay particular attention to the fuel pressure sensor on the fuel rail and the fuel pressure sensor wiring harness.

Were any signs of tampering discovered?

No

Replace the Fuel rail pressure sensor.

Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)



Yes

Restore Fuel system to original condition.

Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

 

[DavidStevenson]

tHANKS FOR THE INFO

 

[RonCar]

I have had this code with NO check engine light for like 6 months. I took it to dealer when I first saw it by turning the key 3 times. They told me I should not be checking the codes like that and not to worry about it! What is up with this code and why hasn't mine cleared after so many cycles of the key (starts)????

 

[macdaddy]

"Common rail pressure sensor performance"



Had it also.



Roncar you'll need a scanner to clear it. I believe multiple ignition cycles only clears the check engine light, not the stored code. At least thats the way my 05 went when I took care of the problem.



I also hear that this is a common code and that in most cases the sensor is fine.



No worries!!!!!



Mac

 

[donnier]

FYI,

IV had the same code on my 05 three times.

The first time was in April. Went to the dealer and they told me what it was, cleared the code and ordered a sensor.

Three months later, same code. Back to dealer, sensor changed.

Two months later, same code, back to dealer.

Dealer said DC is aware of the prob and working on a fixit but none as of yet.

Said it would not hurt to drive it. If it happens again to bring it in and have it cleared.

 

[Bob4x4]

The logic for that code is not correct. The ECM wants to see rail pressure with key on,not running... ... ... ... it AINT going to happen. I suspect if you turn key on and wait to crank will be the condition it sets.



Bob