P0349

Code

Generic P — Powertrain

Camshaft Position Sensor A Circuit Intermittent Bank 2

Brand: Generic

Type: P — Powertrain

Views: UK: 25 EN: 37 RU: 37

AI status

Completed

ready

Completed 100%

Page language: EN

Damaged or corroded sensor connector or pins
Broken, chafed or shorted wiring harness between the sensor and PCM
Loose, intermittent or missing ground or 5V reference supply
Faulty camshaft position sensor (Bank 2, Sensor A)
Intermittent internal PCM/ECM fault or poor PCM connector contact
Physical timing/valvetrain issue (worn timing chain, broken tooth, cam phaser problem)

Check Engine Light (MIL) with code P0349 stored intermittently
Engine may start but run poorly or misfire under certain conditions
Hard starting, stumbling or rough idle that comes and goes
Loss of spark or fuel control in extreme cases if PCM relies on cam signal for injection/timing
No noticeable driveability change until signal loss becomes sustained

Read freeze frame and live data to see operating conditions when code set
Clear codes and perform a driving cycle to reproduce the fault
Visually inspect sensor and connector for damage, corrosion, oil or water intrusion
Backprobe sensor connector and monitor signal while cranking and at idle with a scan tool or oscilloscope
Wiggle test wiring and connector while monitoring signal / DTC to catch intermittent opens/shorts
Check for proper 5V reference and ground at the sensor connector with key ON, engine OFF

Hall-effect type: digital square wave ~0–5 V (logic low to logic high) with frequency proportional to engine RPM
Variable reluctance (VR) type: AC waveform; small VAC at cranking (≈0.2–1.5 VAC) increasing with rpm; frequency rises with engine speed
Expected behavior: stable, consistent waveform while cranking and at idle; no intermittent dropouts or noise spikes
Reference circuits: sensor typically has a 5 V reference (supply), ground, and signal — supply should be ~5 V with key ON; ground should be near 0 V
If using a scope: clean edges on Hall sensors, consistent amplitude and timing relative to crankshaft signal; intermittent gaps or noise indicate wiring/sensor issues

Connect a scan tool, record freeze frame and live PCM data for cam/crank signals; note conditions when DTC set
Visually inspect the Bank 2 Camshaft Position Sensor A connector and wiring for corrosion, bent pins, oil/water, or physical damage
With connector disconnected, check for 5 V reference and good ground at the sensor harness with key ON (do not short pins)
Backprobe the signal wire and observe with an oscilloscope or multimeter while cranking/idle; look for stable waveform and no intermittent dropouts
Perform a wiggle test: move wiring harness and connector while monitoring signal and DTC history to reproduce intermittent behavior
Measure continuity and resistance from sensor connector to PCM pin to check for intermittent open or high resistance; inspect harness routing for chafe/heat damage
If VR sensor, measure AC output while cranking; if Hall sensor, confirm switching between ~0 and ~5 V
Swap with a known-good cam sensor (if identical and accessible) or temporarily substitute to see if fault clears
If wiring and sensor check good but intermittent persists, inspect cam timing components (timing chain/belt condition, phaser) for mechanical cause of intermittent signal
If all else passes, test/inspect PCM connector for poor contact or consider PCM fault — follow manufacturer procedures before replacing PCM