Code for fuel pressure regulator.

[RyanD77968]

My 2014 1500 is throwing a code for the fuel regulator and I’m not sure where it is. I’ve changed out the high pressure sensor but no luck. Any advise. 

[newdude]

What is the code you have?

 

[RyanD77968]

It’s P0091. 
 

 

[RyanD77968]

It’s P0091. 
 

I just dug around some more and noticed it may be either the high pressure fuel pump or a bad connection to the harness. If anyone has more knowledge on the topic it would be appreciated. 

[newdude]

 

28 minutes ago, RyanD77968 said:

It’s P0091. 
 

 

 

 

DTC P0091

Fuel Pressure Regulator Control Circuit Low Voltage

 

Description

Fuel Pressure Regulator — G18 High Pressure Fuel Pump

The fuel pressure regulator is a solenoid valve that restricts the flow of fuel to the high pressure fuel pump and thereby controls the pressure the pump can produce.  The fuel pressure regulator is a part of the high pressure fuel pump. The fuel pressure regulator is the solenoid valve that controls the pressure in the fuel rail.

 

Diag chart has you test the wiring to the high pressure pump and its control from the ECM.  If all the wiring is good, needs a high pressure fuel pump.  

 

Testing of the pump below:  

 

Note: The component's temperature should be 19 to 21°C (66 to 70°F) while testing.

1. Ignition/Vehicle & All vehicle systems » Off
2. Disconnect the electrical connector: G18 High Pressure Fuel Pump
3. Test for 0.58 to 0.7 Ω between the test points: Control terminal 1 & Control terminal 2
   • If not between 0.58 and 0.7 Ω

     Replace the component: G18 High Pressure Fuel Pump

   • If between 0.58 and 0.7 Ω
4. Test for infinite resistance between the test points: Each terminal of the component & The component's housing
   • If less than infinite resistance

     Replace the component: G18 High Pressure Fuel Pump

   • If infinite resistance
5. All OK.

Edited March 4, 2022 by newdude

[Tony Duplechain]

I have a 2015 GMC Sierra Denali 1500 6.2 liter. Can the fuel pressure regulator cause it to have a rough idle, like it has a miss. 

 

[silveradosid]

yes, if the pressure is low you could have miss fires