P0344moderate severityGenerally driveableP0344 Code: Camshaft Position Sensor Circuit Intermittent (Bank 1)
Written in plain English and reviewed by the eli5cars editorial team · Last reviewed June 2026
What it means in plain English
The camshaft position sensor tells the ECM exactly where the camshaft is in its rotation, which it uses — along with the crankshaft position sensor — to time fuel injection and ignition correctly and to sequence fuel delivery to the right cylinder at the right moment. P0344 means the signal from the Bank 1 camshaft position sensor is dropping out or cutting in and out intermittently, rather than failing completely or being missing outright. Because it's intermittent, this code can be trickier to pin down than a dead-signal code — it often only shows up under specific conditions like engine heat, vibration, or a particular RPM range.
Most likely causes — ranked
#1 Damaged, corroded, or loose wiring/connector at the Bank 1 camshaft position sensor
most likelyFix: An intermittent signal points strongly at a wiring or connection problem rather than a fully dead sensor. Inspect the connector for corrosion or a loose latch, and check the harness for chafing where it runs near hot or moving engine components. With a scan tool showing live cam sensor data, gently wiggle the harness near the sensor and connector — a signal that drops out as you do this confirms a wiring fault.
#2 Camshaft position sensor tip contaminated with oil or metal debris
likelyFix: On many engines the cam sensor sits near the valve cover or timing cover, where a nearby oil leak or normal seepage can coat its sensing tip. Contamination on the tip can cause an inconsistent signal that comes and goes as debris shifts. Remove the sensor, clean the tip carefully per manufacturer guidance, and inspect for the source of any oil leak nearby before reinstalling.
#3 Failing camshaft position sensor with an internal fault that worsens with heat
likelyFix: If wiring and contamination are ruled out, the sensor's internal electronics may be intermittently failing — a common pattern is a code that only appears once the engine has fully warmed up. Replace the sensor; it's usually a simple one-bolt job accessible from the top or side of the engine.
#4 Timing chain wear affecting the sensor's tone-wheel alignment
possibleFix: Less commonly, a stretched timing chain shifts the reluctor or tone wheel the sensor reads just enough to cause an inconsistent signal without a full correlation-code failure. Have a shop check for a measurable cam-to-crank timing offset with a scan tool if the sensor and wiring both test fine.
Check engine light on? Get a free code scan
If your check engine light is on, most auto-parts stores (AutoZone, O'Reilly, Advance) will read the code for FREE — no purchase required, just walk in. Bring the code back here and look it up at eli5cars.com/obd2 for the plain-English explanation.
Note: a scan only helps when there's an active fault code. For purely mechanical symptoms (noises, vibrations, leaks), a scan may show nothing — the suspects listed above are your starting point.
Want to read the codes yourself?
First, the free option: AutoZone, O’Reilly, and Advance Auto Parts read your codes for free — no purchase needed. That’s the cheapest way to get the code to look up here. If you’d rather have your own so you can check anytime (and clear a code after a fix), the Veepeak OBDCheck BLE is an inexpensive, reliable plug-in reader that pairs with a free phone app and works on any car sold since 1996.
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Frequently asked questions
Can I drive with P0344?
Usually yes for now, but don't put off diagnosis. An intermittent cam sensor signal can, in some cases, cause the engine to stall unexpectedly or have trouble restarting if the dropout happens at the wrong moment. If you notice stalling or hesitation along with this code, get it looked at soon.
Why does the code say 'intermittent' instead of just 'malfunction'?
It reflects what the ECM actually observed — the signal came and went rather than disappearing completely or being permanently out of range. That distinction is a useful diagnostic clue: it usually points toward a wiring or contamination issue rather than a sensor that's fully dead.
How do I catch an intermittent fault during diagnosis?
A scan tool with live data is essential. Watch the camshaft position signal while wiggling the connector and harness, revving the engine, and letting it reach full operating temperature — intermittent faults often only show up under one of these specific conditions.
Will a bad cam sensor affect the crankshaft position sensor too?
No, they're separate circuits, but the ECM cross-checks the two signals against each other. A cam sensor problem can sometimes also trigger a correlation code, such as P0016 or P0017, alongside P0344 — note any additional codes present when you get it scanned.