P0348 — Camshaft Position Sensor A Circuit High Input (Bank 2)

Does P0348 always mean the Bank 2 camshaft sensor is physically broken?

No. P0348 can also result from a signal wire shorted to supply voltage, a poor ground, an open circuit, or a damaged connector.

Can I continue driving with P0348 stored?

If the engine runs smoothly, limited driving to a repair shop may be reasonable. Stop driving if the engine stalls, runs severely rough, or loses substantial power.

What electrical condition does P0348 identify?

P0348 identifies an abnormally high input on the Bank 2 camshaft position sensor A circuit, not necessarily a mechanical timing failure.

Will clearing P0348 with a scanner repair the fault?

No. Clearing P0348 only erases the stored code; it will return if the high voltage, wiring, connector, ground, or sensor fault remains.

When your engine control unit decides something looks wrong with the camshaft position sensor circuit on the exhaust side of the engine, it logs trouble code P0348. This specific code flags the "A" sensor on Bank 2—the bank that does not contain cylinder number one. The ECU expects to see a specific voltage pattern coming from that sensor as the camshaft spins; when the signal stays persistently high or behaves erratically, P0348 gets stored and the Check Engine light illuminates.

Modern engines rely heavily on camshaft position data to orchestrate variable valve timing, which optimizes power delivery and fuel economy across different driving conditions. The sensor itself is a small, feedback device mounted near the camshaft phaser. It generates a digital or analog signal that tells the engine computer exactly where the camshaft is positioned at any given moment. If this signal reads outside the factory-defined window—staying high when it should be toggling, for instance—the ECU interprets this as a fault. On some platforms, a failed cam position sensor can also prevent the variable valve timing system from operating correctly, since that system depends on precise cam timing data.

The way the ECU handles this fault is consistent across most manufacturers. After the abnormality is detected through multiple drive cycles, the code is permanently stored, and a freeze frame snapshot is captured. That snapshot records RPM, engine load, coolant temperature, vehicle speed, and other sensor readings at the exact instant the problem occurred. This data is your most valuable starting point when you connect a scan tool, because it tells you whether the fault happened at idle, under heavy load, or during a specific temperature range.

Common Symptoms of P0348

When P0348 is active, drivers typically notice one or more of the following issues:

• The engine runs roughly at idle, with a noticeable tremor or stumble
• Acceleration feels sluggish, especially in the low-to-mid RPM range
• Fuel economy worsens noticeably compared to normal driving
• The engine takes longer than usual to start, sometimes requiring extended cranking
• The Check Engine light stays illuminated on the dashboard
• In some cases, the engine may enter a limited-power failsafe mode

What Causes P0348

The root cause could be electrical, mechanical, or hydraulic. Here are the most frequent culprits, listed from most to least common:

• Dirty or low engine oil — Variable valve timing systems use oil pressure to actuate phasers. Contaminated oil clogs small passages and prevents proper timing adjustment, which can indirectly affect sensor readings and trigger P0348.
• Failing camshaft position sensor — Age, heat exposure, and internal wear can cause the sensor's output to drift high or go completely silent.
• Faulty VVT oil control valve — This solenoid regulates oil flow to the cam phaser. When it sticks or clogs, timing behavior becomes erratic, sometimes confusing the ECU into setting P0348.
• Worn or failed cam phaser — Mechanical wear inside the phaser assembly can throw off the relationship between commanded and actual cam position.
• Wiring or connector issues — Damaged harness insulation, corroded pins, or loose connectors can create high-resistance faults that mimic a sensor failure.
• Timing chain or belt stretch — If the timing drive has jumped a tooth or is excessively worn, cam position readings will no longer match the expected values.
• ECU software glitch — Rare, but some vehicles have had software bugs that falsely flag cam sensor circuits; a reflash or update may resolve it.

How to Diagnose P0348

Follow this systematic approach before replacing any components:

1. Connect an OBD2 scanner and confirm that P0348 is the only stored code. Note the freeze frame data—it reveals the operating conditions when the fault first appeared. This guides your inspection strategy.
2. Check for related diagnostic trouble codes. Secondary codes such as misfire counters or other cam position sensor faults often point toward the actual problem area. Review any technical service bulletins that apply to your vehicle's make, model, and model year.
3. Perform a visual inspection of the wiring harness and connector at the camshaft position sensor. Look for cracked insulation, exposed wires, corrosion buildup, or any signs that the connector is not fully seated.
4. Assess engine oil condition and level. Drain a small sample and check its color and viscosity. If the oil appears black, gritty, or smells burned, change it before proceeding. VVT systems are extremely sensitive to oil quality.
5. Compare live data between commanded and actual cam position using your scan tool's data stream. Rev the engine in neutral and observe whether the actual position tracks the commanded position or lags significantly.
6. Clear the code and drive the vehicle through a complete drive cycle that recreates the conditions captured in the freeze frame. If P0348 returns, you have confirmed a hard fault rather than an intermittent glitch.

Repair Options and Costs

Not every P0348 scenario requires an expensive fix. Work through the most likely causes first:

• Camshaft position sensor replacement — The most common repair. Sensor cost ranges from $50 to $150, with labor adding $70 to $200 depending on engine bay accessibility. Total: $120–$350.
• VVT oil control valve replacement — Often the solution when oil condition is the underlying issue. Parts run $80–$250, labor $120–$250. Total: $200–$500.
• Timing chain or belt repair — Required only if the timing drive itself is at fault. Parts range from $300 to $1,200, with labor from $500 to $1,300 due to significant disassembly. Total: $800–$2,500.

Total repair cost for P0348 falls anywhere between $120 and $2,500 depending on which component is actually faulty. A methodical diagnosis prevents spending $500 on a sensor when the real issue was simply dirty oil and a stuck VVT solenoid.

Can You Drive with P0348?

Drive with caution. The engine may continue running, but performance will likely suffer, and fuel consumption will increase. On interference engines—those where valves and pistons occupy the same space—a jumped timing chain combined with a faulty cam sensor creates a real risk of catastrophic valve damage. Until you confirm whether the timing drive is intact and the oil system is functioning properly, limit driving to essential trips and have the vehicle diagnosed promptly.