No acceleration from the start
 

I have a 2004 6.0l powerstroke diesel.

When I bought it it ran great. Shortly after the pulley on the AC unit went out. Had a new AC unit installed and now i have no acceleration from a dead start. Seems that when i depress the accelerator, I get very slow accel. Even putting the pedal to the floor shows the tach climb but no accleration. It shifts fine and when i let up on the gas i get a shift and a little acceleration.

Tried a new movable pedal, didnt change anything. Also no codes. everything else is stock. Only thing I have found is a sticker saying the PCM was reprogrammed. Did not have this problem before the AC unit was installed.

Any ideas? Very new to diesels in general.

Make sure the MAP hose is plugged into the MAP sensor, and that the hose is not cracked or plugged up.

KOEO - post MAP, EBP, Baro readings

ok. i am going to get new hose for it this weekend and just replace the vacuum line.
How do i get those numbers your asking for? MAP, EBP, Baro readings

Vacuum on the 6.0L is used only for 4x4 hub operation, for climate control operation, and for the heater hose valve.

MAP, Baro, and EBP are obtained by getting a scan tool that reads live engine parameters (PIDs). All 6.0L owners need this type of electronic gauge system.

Choices:

ScangaugeII, Edge CTS

Phone or Tablet Apps - Torque, Forscan, DashBoss

i meant that i will just replace the hose to the map sensor so i can eliminate that item and i will get a scanner this weekend. Hopefully i can find the problem soon.

Got this issue resolved. Turns out that the high pressure oil pump and relay was shot. no low end oil pressure for the acceleration. A pricey fix but it is fixed and i no longer have a paperweight in my yard. All I have left is to replace the #8 injector and I have a 100% running truck.

Glad it is fixed. What relay are you referring to? The HPOP is gear driven.