Air fuel control derate?

[Rockycoon75]

(06-04-2017 )Rawze Wrote:  

(06-04-2017 )Rockycoon75 Wrote:  Imap new on the 17th. Air to air tested good.
Fuel pressure at 1800 is 276 so in range but on The bottom end The derate and low power will last all the way through the low side usually starts to pick up and go when i get to the high side.

Since you have cummins insite, monitor the VG position commanded and the VG positiion measured and see if they are matching when it is acting up. Also pay attention to the position measured and see where it is going compared to when it is running right.


A miss-match of more than about 1-2% is not a good sign. 5% or more of mismatch and it is definitely the turbo acting up.

Commanded and actual are mostly the same. Sometimes they are + - 1 but on the next refresh they are the same. Some dust clinging around gear pump seam. Cleaned everything off and will see if it happens again. No wetness found elsewhere.

Could fuel actuator cause these problems? They look original so have 755k on them