I know that in the 2003 Dodge FSM the specification for fuel pressure is 9.5 PSI Minimum. I know that future books, like 2004 and forward, do not list fuel pressure specifications. I'm going to call the minimum pressure for a common rail engine a minimum of 10 PSI. I'm going to aim for 15 PSI with the AirDog 150. Problem I'm pretty sure I got a tank of debris fuel and most likely the fuel filters are plugging up and causing the grid heater light to come on because the demand pressure on the rail is not stable so the 2012 firmware update that creates the P2122 and P2123 codes is watching the pressure on the rail and when the rail cannot reach target or the rail pressure is swinging too low in pressure between injectors events.
Here we go gang I'm going to start an article based on this and build a fuel pressure article for 3rd Gen trucks so people can get help with grid heater light, P2122 or P2123 codes.
The return fitting of the AirDog was removed, and the check ball was found stuffed in the coil of the spring. I modified the spring by bending the last coil over so the arm of the coil blocks the center of the coil, so the check ball rides on the top of the spring. Then the spring was shimmed with 2 washers like I did on Beast. Barely gave me 10 PSI by the time I got to Riggins, ID. It dropped to 5 PSI of fuel pressure.
I plan on replacing all filters again. Both AirDog filters and the engine fuel filter, too. I gotta call my local NAPA store with the part numbers I have on the website. Replace all the filters and try again.
I know that in the 2003 Dodge FSM the specification for fuel pressure is 9.5 PSI Minimum. I know that future books, like 2004 and forward, do not list fuel pressure specifications. I'm going to call the minimum pressure for a common rail engine a minimum of 10 PSI. I'm going to aim for 15 PSI with the AirDog 150. Problem I'm pretty sure I got a tank of debris fuel and most likely the fuel filters are plugging up and causing the grid heater light to come on because the demand pressure on the rail is not stable so the 2012 firmware update that creates the P2122 and P2123 codes is watching the pressure on the rail and when the rail cannot reach target or the rail pressure is swinging too low in pressure between injectors events.
Here we go gang I'm going to start an article based on this and build a fuel pressure article for 3rd Gen trucks so people can get help with grid heater light, P2122 or P2123 codes.
Video
https://youtube.com/shorts/Iw3iiLTI-GY?feature=shared
What has been done so far...
The return fitting of the AirDog was removed, and the check ball was found stuffed in the coil of the spring. I modified the spring by bending the last coil over so the arm of the coil blocks the center of the coil, so the check ball rides on the top of the spring. Then the spring was shimmed with 2 washers like I did on Beast. Barely gave me 10 PSI by the time I got to Riggins, ID. It dropped to 5 PSI of fuel pressure.
I plan on replacing all filters again. Both AirDog filters and the engine fuel filter, too. I gotta call my local NAPA store with the part numbers I have on the website. Replace all the filters and try again.
Edited by Mopar1973Man