DES FPR won't go over 10k

[hopkins_fam]

So I'm driving from work and noticed on my Outlook the FPR didn't go over 10k. so i change my filters and dose it with 911 and stull nothing. i throw my xcelerator on and desired never gets abovee 10,150. pedal shows good, she makes boost, MAF is moving like it should, intake temp was around 46 which it was about 5 degree outsidde and fuel temp was 89. What's going on?

Could it be rail sensor, fpr, or ficm?

 

[catman3126]

It must be going over 10K if your making good power. it would be a turd at 10K.

 

[onebaddmaxxx]

Unplug the fpr plug and see if it will command 23k.

 

[NinjaMax]

Mine had a problem with a fuel temp sensor....didn't have a code showing..was only getting a little over 10k rail pressure...we "cleared" the code and its been fine every since... Just an idea...good luck

 

[DAVe3283]

Unplugging the FPR will not change the commanded value. It will change the actual.

To diagnose a FPR, you need to compare the desired and the actual rail pressure values. If the commanded is only 10k PSI, that doesn't mean a bad FPR. It might indicate some other problem(s), but not the FPR.

If you have EFILive (or any other scan tool capable of this), please use that to command 23k PSI instead of unplugging the FPR. Unplugging the FPR is a good quick diagnostic, but is hard on the CP3 and pressure relief valve. Commanding a high pressure with a scan tool is just fine.

 

[hopkins_fam]

Guess it was fuel temp. I got a fuel temp code a while back the first time I removed the PPE from the truck. A mbr from BT Diesel suggested it was fuel temp, and another mbr stated a while hack that the PPE ignores some values like fuel temp and EGR.

So to test the theory this morning I threw the tuner back on and tuned to level 1 and rail pressure is back to normal.



Sent from my PG86100 using Tapatalk

 

[NinjaMax]

Nice:thumb:

 

[duratothemax]

glad to hear that the fuel temp sensor was the issue!

Ben