Between Omaha and Des Moines, 7 miles South of I80 | Sounds like the CAT ECM can't see vehicle speed (MPH), So the ECM "thinks" the truck is always standing still (0 MPH) thus the cruise swithes are only acting like they are in PTO MODE, and the ECM is SET/programmed to 1400 RPM in PTO MODE, thus that is all the RPMs that you can get out of the truck, whether stilling still OR driving=ECM thinks truck is at 0 MPH.
Jakes, did you hook up the wires, to jake solenoids, under valve covers? |
Peterbilt 379 cruise control
