Engine management · Severity: Moderate
P0340 — Camshaft Position Sensor A Circuit
The ECU sees no signal or an implausible signal from the camshaft position sensor.
Common symptoms
- Long cranking
- Hard starting
- Stalling
- Reduced power
Likely causes
- Failed cam sensor
- Wiring/connector fault
- Oil in the connector
- Timing issue
First test to run
Verify 5 V reference and ground at the sensor connector, then scope the signal while cranking.
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