OBD-II trouble code
P0346: Camshaft Position Sensor 'A' Circuit Range/Performance (Bank 2)
The 'A' camshaft position sensor on Bank 2 is sending a signal, but it's out of range or doesn't line up with the crankshaft. It can cause hard starting, stalling, rough running, or reduced power.
Quick facts
- System
- Powertrain
- Category
- Camshaft / Timing
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $40 – $400
- DIY difficulty
- Intermediate DIY
What does P0346 mean?
The camshaft position (CMP) sensor reports the exact rotational position of the camshaft to the engine control module (ECM). The ECM combines that with the crankshaft position signal to know which cylinder is on its compression stroke, which lets it fire the correct fuel injector and ignition coil at the right moment and, on many engines, control variable valve timing. P0346 is a 'range/performance' fault: unlike a dead-circuit code, the ECM is receiving a signal from the 'A' camshaft sensor on Bank 2, but the signal is out of its expected range, erratic, or doesn't correlate properly with the crankshaft position.
Bank 2 is the side of the engine that does NOT contain cylinder number 1, so P0346 applies to V6, V8, and other V-configuration or some horizontally-opposed engines that have camshaft sensors on both banks. It is the Bank 2 counterpart to P0341, which describes the same range/performance fault on Bank 1, and a close relative of P0345 (Bank 2 'A' camshaft circuit), which flags a more basic circuit fault. The 'A' designation refers to a specific camshaft — typically the intake cam, or the sole cam on a single-cam-per-bank design — as defined by the manufacturer.
Because this is a correlation and performance fault rather than a total signal loss, the cause is often mechanical or timing-related as much as electrical. A stretched or jumped timing chain, a worn variable-valve-timing phaser, low or dirty oil affecting a phaser, or a damaged reluctor/tone ring can all make the cam signal drift out of its expected relationship with the crank. That means P0346 should be diagnosed carefully rather than fixed by simply replacing the sensor, because a new sensor won't cure a timing or oil-related problem.
Common causes
- Failed or weak Bank 2 'A' camshaft position sensor
- Stretched or jumped timing chain/belt throwing off cam-to-crank correlation
- Worn variable-valve-timing phaser or actuator on Bank 2
- Low or dirty engine oil affecting a VVT phaser the sensor reads
- Damaged reluctor/tone ring on the camshaft, or a chipped tooth
- Damaged, chafed, or corroded sensor wiring or connector
- Metal debris or oil contamination on the sensor tip
Symptoms
- Check engine light is on
- Hard starting or extended cranking
- Engine stalling, stumbling, or rough idle
- Reduced power or hesitation on acceleration
- Intermittent misfire feel
- Possible drop in fuel economy
Diagnostic steps
- 1.Scan for all stored codes. Address any crankshaft position (P0335-series) or timing-correlation (P0016/P0018/P0019) codes together, since they interact with the cam signal.
- 2.Check engine oil level and condition first — low or sludgy oil is a common, cheap cause of VVT-related cam correlation faults.
- 3.Inspect the Bank 2 camshaft sensor connector and wiring for damage, oil intrusion, corrosion, or chafing.
- 4.With a scan tool, watch the camshaft sensor signal and cam-to-crank correlation data while the engine runs to see where the signal drifts out of range.
- 5.Remove and inspect the sensor tip for metal debris or damage; inspect the reluctor/tone ring for chipped or missing teeth.
- 6.If the sensor, oil, and wiring all check out but a correlation fault remains, investigate timing chain/belt stretch or phaser wear before replacing more parts.
Repair cost
$40 – $400
The camshaft position sensor itself is often $40 to $200 in parts, with 0.5 to 2 hours of labor depending on how buried it is, so a straightforward sensor replacement is commonly $150 to $350 total. Wiring repairs run $50 to $200. If the cause is a stretched timing chain or a worn VVT phaser, the repair is substantially more expensive and is diagnosed and quoted separately.
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.