OBD-II trouble code
P0344: Camshaft Position Sensor "A" Circuit Intermittent (Bank 1)
The bank-1 camshaft position sensor signal is cutting in and out. The defining trait is 'intermittent' — it works most of the time, then briefly drops or glitches before recovering. That makes it the trickiest of the cam-sensor codes to pin down, because the fault is often gone by the time you test, and the usual culprits are a loose connector, a chafed wire, or oil intrusion rather than a flat-dead sensor.
Quick facts
- System
- Powertrain
- Category
- Sensors / Timing
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $110 – $450
- DIY difficulty
- Intermediate DIY
What does P0344 mean?
P0344 is the 'circuit intermittent' member of the bank-1 camshaft position sensor 'A' family. The CMP sensor reports camshaft position so the PCM can identify cylinder sequence for sequential injection and manage variable valve timing. Where P0342 and P0343 are steady level faults (too low, too high) and P0341 is a steady range/performance fault, P0344 means the signal momentarily drops out or glitches and then comes back. The PCM sees a brief, impossible interruption in the cam signal, flags it, and may momentarily lose cam sync before recovering.
The intermittent character is the whole story and steers diagnosis toward connection problems rather than a dead part. A loose or corroded connector that makes and breaks contact, a wire that's chafed or cracked and only opens when it flexes or heats up, and intermittent electrical noise are the classic offenders — the same pattern behind any intermittent circuit code. Because cam sensors frequently sit in oily areas, oil seeping into the connector or onto the sensor tip is a common cause that comes and goes with temperature. A sensor beginning to fail can throw an occasional glitch before it dies, and a marginal air gap or a reluctor with one damaged tooth can produce a dropout tied to vibration or heat. A static bench test often passes because the fault isn't present at that moment.
For the driver, P0344 shows up as occasional hard starts, a momentary stumble or hesitation, a brief loss of power, and a check engine light that may come and go. The engine usually keeps running between events because it can fall back on the crank signal, so it's generally driveable, though some vehicles may stumble or briefly stall during a dropout. Catching it means chasing the fault while it's happening: freeze-frame data, a recorded live-data drive that reproduces the glitch, and a wiggle-test of the connector and harness while watching the cam signal are far more useful than a one-time resistance check that passes.
Common causes
- Loose or corroded connector at the cam sensor making intermittent contact
- Chafed or cracked wire that opens only when it flexes or heats up
- Oil intrusion into the connector or onto the sensor tip
- Intermittent electrical noise on the sensor circuit
- Sensor beginning to fail and dropping out occasionally
- Marginal air gap or a single damaged tooth on the reluctor
- Moisture intermittently bridging connector pins
Symptoms
- Check engine light that may come and go, with P0344 stored
- Occasional hard start
- Momentary stumble, hesitation, or brief power loss
- Brief loss of cam sync or variable valve timing during a dropout
- Symptoms tied to bumps, temperature, or vibration
- Fault often absent when the engine is tested cold and stationary
Diagnostic steps
- 1.Pull freeze-frame data first — it captures the conditions present when the intermittent dropout set, the best clue for this code.
- 2.Read cam-sensor live data on a drive that reproduces the symptom and watch for momentary signal drops.
- 3.Wiggle-test the sensor connector and harness while watching live data — a glitch during the test localizes a bad connection.
- 4.Inspect the connector for corrosion, backed-out pins, oil intrusion, and moisture.
- 5.Check the air gap and the reluctor for a single damaged tooth that would glitch intermittently.
- 6.Resistance-check the sensor and wiring, looking for a reading that drifts or only goes out of spec when flexed or warm.
Repair cost
$110 – $450
Because P0344 is usually an intermittent connection, wiring and connector repairs are a common and relatively cheap fix at $80-$250 — sometimes just cleaning oil from a connector or re-pinning it. A camshaft position sensor replacement runs $120-$350 if the sensor is dropping out. Budget some diagnostic labor, since the hard part of an intermittent code is catching the fault while it's actually happening.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with camshaft position sensor replacement preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.