Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Fails Emission Test

NOTE: The systems that could be the source of the symptoms are listed and should be checked in the order they are listed, beginning with # 1.

1. Emission Control System
a. Evaporative Emission Controls
b. Catalytic Converter
2. Manifold Absolute Pressure (MAP) Sensor (code 3,5)
3. Fuel Supply System
a. Pressure Regulator
b. Fuel Injector
c. Injector Resistor
4. Heated Oxygen Sensor (code 1,41,43,48)
5. Idle Control System
a. Hoses and Connections
6. Engine Control Modules (ECM) (BU)

Back-up (BU) code used when the MALFUNCTION INDICATOR WARNING LAMP is on, and the self-diagnosis indicator LED is ON with no "blinks", the back-up system is in operation.

NOTE: On Canadian models the MALFUNCTION INDICATOR WARNING LAMP is the CHECK ENGINE LAMP.