OBD-II trouble code
P0349: Camshaft Position Sensor "A" Circuit Intermittent (Bank 2)
The Bank 2 'A' camshaft signal drops out briefly and then comes back. Nothing is wrong when you go to test it, so this one is diagnosed with recorded data during a drive rather than with a meter in the driveway.
Quick facts
- System
- Powertrain
- Category
- Camshaft / Timing
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $200 – $400
- DIY difficulty
- Advanced DIY
Browse every code in P0300–P0394, or start from the full code library.
What does P0349 mean?
P0349 does not describe a broken circuit. It describes a circuit that works, stops working for a fraction of a second, and works again — and that difference changes the entire approach. Every static test you can perform in a parking lot is being run at the one moment the fault is not present, which is why people replace the sensor, see the light stay off for a week, and then have the code return.
The signal comes and goes with a terminal that has lost tension, a wire broken inside the insulation, or a connector that moves with heat. Capture when it happens from the freeze frame: temperature, rpm, and whether the road was rough. There is no twenty-minute rule. Log the trace or have a passenger watch it. Do not read a scan tool while driving.
That also makes P0349 the member of this family you can never declare fixed by clearing the code and driving for an afternoon. An intermittent that appears once a week looks identical to a repaired car for six days. Say so plainly if you are handing the vehicle back to someone: the honest answer is that confidence comes from reproducing the fault before the repair and then failing to reproduce it afterward under the same conditions, not from a quiet dashboard. There is also a safety dimension worth naming, because on engines that need cam sync to keep running, an intermittent dropout shows up as a stall in traffic with no warning and no other codes stored.
Common causes
- Terminal in the sensor connector that has lost tension and separates under vibration
- A wire broken inside intact insulation, making and losing contact as the engine rocks
- Hardened or missing connector seal letting moisture in only in certain conditions
- Sensor with a marginal internal joint that opens once it heat-soaks
- Harness routed so it rubs a moving component only at particular engine loads
- Loose or corroded engine-to-body ground shared by the sensor circuit
- Small amounts of metal debris on the sensor tip that shift position with vibration
Symptoms
- Check engine light that comes on, then goes out again on its own days later
- A brief stumble or momentary loss of power that clears itself
- Random stalling with no other codes stored, most often at low speed or idle
- Occasional long crank on one start out of many, then normal starts for weeks
- Symptoms that track with rough roads, hot weather, or heat soak after a stop
- No repeatable pattern the driver can describe, which is itself a useful clue
Diagnostic steps
- 1.Do not clear the code before recording freeze frame data. Engine temperature, load and RPM at the moment it set are the most valuable evidence you will get, and clearing destroys it.
- 2.Set up a scan tool to log the camshaft signal, RPM and sync status, then drive the vehicle under the conditions the freeze frame captured rather than idling in a bay.
- 3.With the engine running, wiggle-test the sensor connector and the harness section that follows the engine's motion while watching live data for a dropout.
- 4.Flex the harness against its normal direction of movement, not just side to side. A wire broken inside its insulation often only opens along one axis.
- 5.Check terminal tension in the connector with a matching pin rather than by eye — a spread terminal looks perfectly normal seated in the housing.
- 6.Warm the suspected connector and wire section with a heat gun while monitoring the signal, and cool it with freeze spray, to try to reproduce a temperature-driven dropout.
- 7.Confirm the engine-to-body ground straps are tight and corrosion free before condemning the sensor circuit.
- 8.After repairing, reproduce the original conditions deliberately before returning the vehicle. A clean drive under a different set of conditions proves nothing.
Repair cost
$200 – $400
Parts plus labor for the sensor once the logged trace shows the dropout is in the sensor rather than a terminal. RepairPal's national average is about $224–$326, rounded to $200–$400. A terminal or connector repair can sit under that. The hours are whatever the service information lists for capturing the fault. They are not a fixed one-to-two-hour rule.
Estimate your repair
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Open the Repair Cost Estimator with wiring harness / circuit repair preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an advanced DIY job. It typically requires specialty tools, scan-tool access, lifting equipment, or careful sequencing to avoid causing new failures. Plan for extended downtime and have a backup vehicle. Most owners are better served by a shop that has done this repair before.