Note On Intermittents

Manipulate ISC wiring while observing PCM input EI72 and while observing ISC operation during PCM output EO07. Manipulate TPS wiring and connector while observing PCM parameter ED01 for jumps, skips and/or intermittent behavior.

Ensure TPS is secured to throttle body (both screws tight). Cycle TPS through its full travel while observing parameter ED01 for erratic behavior. Check for proper TPS part number installed on vehicle. Unplug and reconnect TPS, ISC and PCM connectors, and ensure they are latched properly.

Fig 1: PCM Code E055, Schematic, TPS Out of Adjustment

Courtesy of GENERAL MOTORS CORP.

Fig 2: PCM Code E055, Flow Chart, TPS Out of Adjustment

Courtesy of GENERAL MOTORS CORP.

Fig 3: PCM Code E055