The first few things we noticed were slow cranking and the engine was running very poorly. simple service and repair manual guide, The engine had an off-idle tip-in stumble, it would surge during acceleration and cruise, and its power was quite noticeably reduced. The battery was also discharged, having only 12.2 volts at the terminals even with a surface charge just after shutting the engine off. After going over all of the grounds and giving the battery and terminals the attention they needed, we verified the charging voltage and alternator output were good.
But our shifting problems persisted. Look at the wiring diagram in figure 5: The PSOM receives the AC signal from the differential speed sensor and sends out a square wave vehicle speed signal to the PCM.
