P0346 Code: Honda Accord (2018-2023) - Causes, Symptoms & Fixes

No recalls found in NHTSA database

No owner complaints found in the provided NHTSA data for Honda Accord (2018-2023) related to P0346. This means there isn’t documented complaint data in the supplied dataset to indicate prevalence or typical failure patterns. That does not guarantee the issue never occurs; it simply reflects the data you supplied. The information below combines general OBD-II knowledge with Honda-specific considerations and should be used as a diagnostic guide rather than a statistical field guide.

CODE MEANING AND SEVERITY

• What P0346 means:

  • P0346 is the diagnostic code for a Camshaft Position Sensor A Circuit Range/Performance problem. In practice, it indicates that the camshaft position sensor signal (often for Bank 2 or a second sensor on engines with multiple camshafts) is outside expected range or not behaving consistently enough for the engine control module (ECM/PCM) to trust it.
  • On many Honda engines used in Accord models (2018-2023), you’ll encounter this in the context of the camshaft position sensor circuit and timing-related sensing. Depending on your exact engine, “Bank 2” vs. “Bank 1” labeling may be used in service data; the practical effect is that the cam timing signal from a cam position sensor is not within expected parameters.

• Severity and symptoms you might see:

  • Check Engine Light (CEL) or MIL illuminated
  • Misfires, rough idle, or erratic engine behavior
  • Difficulty starting, intermittent no-start
  • Power reduction or limp-home behavior in some cases
  • Engine stall or surging in certain driving conditions
  • Infrequent cases, no obvious drivability symptoms if the fault is intermittent

• Important note about the data:

  • The provided dataset shows no NHTSA complaints and no recalls for this exact issue on 2018-2023 Accord models. Real-world prevalence can differ; use this guide as a diagnostic resource rather than a statistical forecast.

COMMON CAUSES ON HONDA ACCORD

• Faulty camshaft position sensor (CMP) itself
• Damaged or corroded CMP wiring harness or sensor connector
• Loose, damaged, or unplugged electrical connectors (ground or signal wires)
• Timing-related issues (timing chain/belt misalignment or tensioner problems) leading to out-of-range cam timing
• Variable Valve Timing (VVT) system faults (e.g., stuck or sluggish VVT actuator/solenoid)
• Low or dirty engine oil affecting VVT solenoids or cam timing operation
• PCM/ECU software calibration or intermittent electrical interference
• Intermittent faults that only show up under certain RPM/engine load conditions (making diagnosis trickier)

SYMPTOMS TO WATCH FOR

• Illuminated check engine light with P0346 in the PCM fault memory
• Rough idle or fluctuating idle speed
• Hesitation, reduced power, or poor acceleration
• Misfires on one or more cylinders (you might see misfire codes too, such as P030x)
• Hard starting or occasional stalling
• Deteriorating fuel economy
• Occasional no-start condition (rare but possible with cam timing signal loss)
• No obvious mechanical noise; electrical symptoms are common

DIAGNOSTIC STEPS (step-by-step guide)

Note: Begin with non-invasive checks and move to more involved tests only as needed. Document data as you proceed.

A. Prepare and verify

• Use a quality OBD-II scanner to confirm P0346 and record freeze-frame data, live sensor readings, and any related codes (e.g., P0010, P0011, P0340, P0335).
• Check the engine oil level and oil quality. Ensure oil meets Honda spec and is not excessively dirty or old; VVT systems rely on proper oil pressure/quality.

B. Visual and electrical inspection

• Inspect the CMP wiring harness for wear, fraying, heat damage, or pin corrosion at the sensor connector.
• Disconnect and re-seat the CMP connector carefully to ensure a solid electrical connection.
• Look for oil leaks or contamination around the sensor and its connector (oil can cause degraded electrical contact).
• Inspect ground connections and battery voltage; ensure the ECM/PCM has a solid ground reference.

C. CMP sensor testing (non-destructive electrical checks)

• With ignition off, back-probe the CMP connector to verify:
  • Reference voltage (typically ~5V) from the ECM to the sensor
  • Ground connection present
  • Signal output changes as you rotate the engine or manually manipulate the sensor area (some vehicles require crank/valve timing to observe changes)
• If you have an oscilloscope, you can observe the CMP waveform while cranking or running; an abnormal or absent signal indicates a faulty sensor or wiring issue.
• If the sensor is easily accessible, you can perform a swap test with a known-good sensor when feasible (if you have spare parts from a similar engine and tool access).

D. Mechanical timing considerations

• A P0346 fault can be related to cam timing or a stuck cam phaser in VVT-equipped Hondas. If the engine’s timing is significantly off, it can generate cam signal range problems.
• If you suspect timing issues:
  • Refer to the Honda service manual for your exact engine code (1.5L turbo or 2.0L turbo variants) for the correct procedure to verify timing marks, camshaft alignment, and tensioner condition.
  • Do not adjust timing without proper procedure and marks; incorrect timing can cause severe engine damage.
• Check for symptoms of a stuck VVT valve/solenoid or oil flow problems (coking, sludge, or poor oil pressure). If oil is dirty or varnished, perform an oil change and inspect/clean relevant solenoids.

E. Related systems cross-check

• Scan for P0010/P0011 or P052B P052C (VVT-related codes). If these codes appear, the issue may involve the VVT system rather than the CMP alone.
• If misfires or ignition issues are present, also inspect ignition coils and spark plugs for wear or damage.

F. Decision point

• If CMP sensor and wiring tests pass and timing appears correct but P0346 persists, you may have an ECU/PCM fault or a subtle timing/valve issue that requires professional diagnostics (scope-based waveform analysis and timing checks).

G. Repair testing and verification

• After performing repairs (sensor swap, wiring repair, or timing/solenoid service), clear codes, perform a test drive across varying RPM/loads, and re-scan to confirm the code does not return.
• Confirm that related symptoms (misfire, rough idle) improve or resolve.

RELATED CODES

• P0340: Camshaft Position Sensor Circuit (General/Bank-1)
• P0341: Camshaft Position Sensor A Circuit Range/Performance (Bank 1)
• P0345: Camshaft Position Sensor A Circuit Low (Bank 1)
• P0010 / P0011: Camshaft Position Actuator / Variable Valve Timing issues (Bank 1)
• P0335: Crankshaft Position Sensor A Circuit Malfunction (as a cross-check if timing/sensor issues are suspected)
  Note: The exact bank designation (Bank 1 vs Bank 2) depends on engine variant. Check your specific Honda engine code to map the correct bank/position.

REPAIR OPTIONS AND COSTS (2025 PRICES)

Prices vary by engine variant (1.5L vs 2.0L turbo), region, and shop. These are representative ranges to help you plan.

• Camshaft Position Sensor (CMP) replacement

  • Parts: typically $40–$150
  • Labor: about $60–$180
  • Typical total: $100–$330
  • Notes: If the sensor is easy to reach, DIY is reasonable; otherwise a shop can handle it.

• CMP wiring harness/connector repair

  • Parts: misc wiring or connector parts, usually $20–$100
  • Labor: $60–$180
  • Typical total: $80–$280

• Timing chain/belt and tensioner (if timing is out of spec)

  • Parts: timing chain/belt kit, tensioners, guides, gaskets ($100–$500 depending on kit)
  • Labor: $300–$1,200 (engine timing work is labor-intensive)
  • Typical total: $400–$1,700
  • Important: This is a substantial repair and should be performed only if timing is actually out of spec or a sensor issue is tied to the timing system.

• VVT solenoid/actuator replacement or cleaning

  • Parts: $60–$180
  • Labor: $60–$150
  • Typical total: $120–$330
  • Notes: If sludge or oil contamination is the cause, an oil change and cleaning may be needed.

• ECU/PCM software update or reflash (if applicable)

  • Parts: minimal; software update cost varies by shop
  • Labor: $50–$150
  • Typical total: $50–$300

• Oil change and filter (as a preventive measure or when diagnosing VVT issues)

  • Parts: oil + filter: $20–$60
  • Labor: $0–$50 (if DIY; otherwise shop labor)
  • Typical total: $20–$110

• Total cost range (rough planning)

  • Sensor/wiring related fixes: roughly $100–$400 (DIY lower end; shop higher end)
  • Timing-related fixes (if needed): roughly $500–$2,000+ depending on scope
  • VVT-related fixes: roughly $120–$350
  • ECU software: roughly $50–$300

DIY vs PROFESSIONAL

• Do-it-yourself (DIY) feasibility:

  • Pros: Lower cost, educational, sensor replacement is often straightforward on many Hondas; quick win if CMP is easily accessible.
  • Cons: For timing chain/belt or VVT work, risk of wrong timing leading to serious engine damage; waveform testing and precise timing checks typically require professional tools and expertise; some Honda engines place sensors in difficult-to-reach locations.

• Professional assistance:

  • Recommended for: suspected timing issues, persistent P0346 after sensor replacement, or if ECU/PCM concerns are suspected.
  • Benefits: Access to service manuals with exact bank designations, specialized tools (scan tools with live data, oscilloscope), and proper torque specs. Diagnostics can be time-consuming; a pro can avoid misdiagnosis and costly mistakes.

• Practical approach:

  • Start with non-invasive, low-cost steps: verify wiring/connector, clean/replace CMP if readily accessible, perform an oil change if overdue, and recheck. If the fault persists or timing/VT issues are suspected, proceed to professional evaluation.

PREVENTION

• Regular oil changes using Honda-approved oil and correct viscosity to ensure VVT system receives proper lubrication.
• Use high-quality, official parts when replacing sensors or related components; avoid questionable aftermarket parts for critical sensors.
• Address oil leaks and engine wear promptly; contaminated oil can affect VVT solenoids and cam timing.
• When performing maintenance, follow Honda’s recommended service intervals and torque specs to avoid loosening or damaging cam timing components.
• If you notice misfires, rough idle, or other drivability concerns, diagnose early rather than letting issues compound.

DATA LIMITATIONS AND DISCLAIMER

• The diagnostic guidance above is built around general OBD-II knowledge and common Honda Accord engine layouts (2018-2023), rather than a data-driven prevalence from NHTSA given in the prompt. The provided dataset shows no NHTSA complaints and no recalls for this issue in this model/year, which limits inference about how often P0346 occurs on these cars.
• Engine variants (1.5L, 2.0L Turbo, etc.) and drivetrain configurations may affect the exact bank designation, sensor location, and troubleshooting approach. Always refer to the specific Honda service manual for your exact VIN and engine code.
• If you’re unsure or uncomfortable with timing-related diagnostics, consult a qualified technician. Timing work on modern engines has real risk if performed incorrectly.

If you’d like, I can tailor this guide to your exact engine code (e.g., 1.5T vs 2.0T) and provide a more engine-specific diagnostic flow, including expected CMP sensor resistance values and bank designation.