Injector Circuit Malfunction - Cylinder 2
P0202 indicates the PCM detected a malfunction in the electrical circuit controlling the fuel injector for cylinder 2. This prevents proper fuel delivery to that cylinder, causing misfires and rough engine operation.
What You Might Notice
- Engine misfire on cylinder 2
- Rough idle or rough running engine
- Poor acceleration and reduced power
- Check engine light (MIL) illuminated
- Possible fuel smell from exhaust
Most Common Causes
- 1
Faulty fuel injector
The injector for cylinder 2 has failed electrically or mechanically, preventing it from opening and spraying fuel. This is the most common cause of this code.
- 2
Open circuit in injector wiring
A break or disconnection in the wiring harness between the PCM and the cylinder 2 injector prevents electrical signal from reaching the injector.
- 3
Short circuit in injector wiring
A short in the injector circuit wiring can cause the PCM to detect an abnormal voltage condition and disable the injector circuit.
- 4
Faulty PCM or connector
A bad connection at the injector connector or a defective PCM driver circuit can prevent proper signal transmission to the injector.
How to Diagnose It
- 1
Check Faulty fuel injector — The injector for cylinder 2 has failed electrically or mechanically, preventing it from opening and spraying fuel. This is the most common cause of this code.
- 2
Check Open circuit in injector wiring — A break or disconnection in the wiring harness between the PCM and the cylinder 2 injector prevents electrical signal from reaching the injector.
- 3
Check Short circuit in injector wiring — A short in the injector circuit wiring can cause the PCM to detect an abnormal voltage condition and disable the injector circuit.
- 4
Check Faulty PCM or connector — A bad connection at the injector connector or a defective PCM driver circuit can prevent proper signal transmission to the injector.
How to Fix It
- 1
Replace cylinder 2 fuel injector
Remove the fuel rail and replace the faulty injector for cylinder 2 with a new or remanufactured unit. This is the most likely repair needed.
- 2
Inspect and repair injector wiring
Check the wiring harness from the PCM to the cylinder 2 injector connector for damage, corrosion, or loose connections. Repair or replace damaged wiring as needed.
- 3
Clean or replace injector connector
Disconnect and inspect the connector at the cylinder 2 injector for corrosion, moisture, or damage. Clean the connector or replace it if damaged.
- 4
Test PCM injector driver circuit
Use a scope or multimeter to verify the PCM is sending the proper signal to the cylinder 2 injector. If the signal is absent or abnormal, the PCM may need replacement.
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