So I have a 98 CCLB 4x4 dually 454. I've had lots of recent maintnenace since purchasing it last fall including front 02's, fuel pump, filter, regulator, intake gaskets, injectors, cap, rotor, wires plugs. In the past 3 months I've had an intermittent low power after a short heat soak. I hooked it up to a fuel pressure gauge and monitored live data today and was able to replicate. Basically after getting it fully warmed up, shut it down for about 5 minutes, start it up and drive away. Starts fine, fuel pressures remained normal over 50 psi at all times. Once accelerating it acts down on power and WILL NOT go above 30 no matter where the throttle is until you get it to about 30, let off, let it shift once and then ease into it. After that, it runs and shifts normally for the duration of the drive cycle. Looking over live data, the only thing I can see that corresponds to the change is the switch to closed loop and I blip the throttle to get it to shift. I have some videos of the the recorded live data on my phone that I'll try to get uploaded. Truck has codes P0161 02 heater circuit b2s2 and P0101 MAF out of range both of which havent set for about 1,000 miles according to freeze frame data. Truck does NOT act like a slipping trans as live data shows rpm and vehicle speed increase proportionately. The TPS doesn't drop out on the scan tool and shows 99% when floored. I'm not sure where to chase this one.
Also got a weird set of U codes today for first time: not corresponding to the ongoing low power problem, U1041 for loss of communication with ebcm and U1192 pass lock loss of comms.
Also got a weird set of U codes today for first time: not corresponding to the ongoing low power problem, U1041 for loss of communication with ebcm and U1192 pass lock loss of comms.
