I have come across a perplexing problem with my late 04 model F250. About two weeks ago my truck started running “different.” Shift point were much higher in the RPM band, turbo farts happened continuously (not just after sudden decel, but while gradual decel too) I have an SCT Livewire and took readings before (when the truck was running “normal”) and after when it started misbehaving. The reading were on the same stretch of road under very similar weather conditions (i.e. flat-straight road, no wind, 80 degrees, cruise set, no A/C)
The before numbers were: idle [-2 to -2.2 psi boost], 75 mph, [9-10 psi boost, 190-192 coolant temp.]
The after numbers were: idle [-1.7 to -1.8 psi boost] 75 mph, [21-23 psi boost, 202-204 coolant temp.]
Boost on a normal accel (exit ramp to highway) went from 18-19 psi to 25-26 psi.
It’s like I’m stuck in a high-boost-high-demand condition. If it were a gasser I would say the choke plate was stuck closed. I replaced the EBP sensor 500-700 miles ago, air filter is clean, no trouble codes (other than a P0000). I am in the process of updating my AutoEnginuity so that hasn’t been run yet. Any ideas??? Coked up turbo ??? whacked sensor??