Note On Intermittents

Manipulate ISC wiring while observing PCM input PI72 and while observing ISC operation during PCM output cycle PO07. Manipulate TP sensor wiring and connector while observing PCM data PD01 (TP sensor). Ensure TP sensor screws are tight. Cycle TP sensor through its full travel while observing PD01 for erratic operation. Check for correct TP sensor part number and ensure connectors are latched.

Fig 1: Code P055 Schematic (DeVille)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code P055 Flow Chart (DeVille)

Courtesy of GENERAL MOTORS CORP.