Test TC-121B: 2/1 Fuel System Lean

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagram, see WIRING DIAGRAMS article.

Inspect all O2S wiring and connectors. Repair wiring and connectors as necessary. Perform TEST VER-5A . If wiring and connectors are okay, perform following tests in order until problem is found:

Ignition system. Perform TEST NTC-2A TEST NTC-2A.
Coolant Temperature Sensor (CTS). Perform TEST NTC-6A .
Manifold Absolute Pressure (MAP) sensor. Perform TEST NTC-8A .
Engine mechanical systems. Perform TEST NTC-13A .
Intake Air Temperature (IAT) sensor. Perform TEST NTC-19A .