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Home >> Cadillac >> 2007 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 28 (Engine Control System - Self-Diagnostics) >> Diagnostic Tests >> DTC P0121: TP Sensor Performance >> Diagnostic Aids
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Diagnostic Aids

WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.

Check throttle valve linkage and lever assembly for free and normal movement. Binding or misalignment of throttle valve can affect TP sensor input. Ensure throttle lever has not been bent or tampered with. Ensure throttle valve opens fully, and lever contacts throttle stop.

On a good TP sensor, scan tool will typically display a TP angle of 8-10 percent at idle, and 76-77 percent at Wide Open Throttle (WOT). An intermittent malfunction may be caused by fault in TP sensor electrical circuit. Check wiring harness and components for an intermittent condition. Repair any electrical circuit faults that were found. Information included in freeze frame data can be useful in determining vehicle operating conditions when DTC first set.