P0346 Code: Chevrolet Cruze (2016-2019) - Causes, Symptoms & Fixes

P0346 – Camshaft Position Sensor “A” Circuit Range/Performance
Chevrolet Cruze (2016–2019)

Important data note

• No recalls found in NHTSA database for this make/model/year/issue.
• No owner complaints listed in the provided data.
• This guide combines the code meaning with Cruze-specific considerations and general, field-tested diagnostic logic. Data limitations mean we rely on typical P0346 behavior and Cruze engine layout, not a vehicle-specific recall or complaint pattern.

CODE MEANING AND SEVERITY

• What the code means
  • P0346 indicates the Camshaft Position Sensor (CMP) A circuit has a range/performance problem. In Cruze engines of this era, this is associated with Bank 1 Camshaft Position Sensor data (the CMP sensor on the camshaft gear provides a signal to the ECU; the ECU uses that timing data to control ignition and fuel injectors).
• Severity and common symptoms
  • Symptoms can range from mild to severe and include: MIL (check engine light) on, rough idle, misfires, hesitation or stumbling during acceleration, reduced power or limp-home mode, hard starting or no-start in some cases.
  • In some situations, the engine may run with this code set but with degraded performance, or it may stall at idle. If the timing reference is out of spec due to a mechanical issue, the symptoms can be more pronounced.

COMMON CAUSES ON CHEVROLET CRUZE

• Faulty CMP sensor (sensor itself is failing or slipping out of spec)
• Damaged or corroded CMP sensor wiring or electrical harness/connectors (insulation wear, chafing, corrosion, poor connector seals)
• Poor/contaminated CMP sensor ground or 5V reference supply feeding the sensor
• Timing-related issues (timing chain/belt stretched or tensioner/slave components worn) causing actual cam timing deviation
• Oil intrusion or excessive oil on the sensor or reluctor ring
• PCM (engine computer) fault or communication issue (less common)
• Mis-installed or damaged timing chain/gear if service has been done and timing marks are off

SYMPTOMS TO CHECK FOR

• Illumination of MIL/CCheck Engine Light
• Rough idle or idle fluctuations
• Stalling or intermittent no-start situations
• Hesitation or reduced power during acceleration
• Misfire codes (P0300-P0306) or cylinder-specific misfire codes appearing with P0346
• Erratic or missing CMP signal in live data (as observed on a scan tool)
• No obvious mechanical damage, but engine timing reference appears out of spec in data stream

DIAGNOSTIC STEPS (structured, practical approach)

Note: This is a general diagnostic flow for P0346 on Cruze. It emphasizes checking electrical integrity first, then sensor function, and finally mechanical timing if required. A capable scan tool with live data and, ideally, oscilloscope capability is very helpful.

A. Verify the code and gather data

• Use a robust OBD-II scan tool to confirm P0346 and review freeze frame data (RPM, engine load, temperature, etc.).
• Check for related/secondary codes (P0340, P0341, P0342, P0345, P0335, P0336, P0300-P0306, P0016, etc.). This helps determine whether the issue is sensor-only or timing/mechanical.

B. Inspect electrical connections and wiring

• CMP sensor connector: disconnect and inspect for corrosion, oil contamination, bent pins, or loose fit. Clean with electronics cleaner and apply dielectric grease if appropriate.
• Check the 5V reference and ground circuit continuity from the PCM to the CMP sensor using a multimeter (back-probe or harness side). Look for:
  • Stable 5V reference (as specified in service information for the Cruze engine family)
  • Good ground connection with low resistance
  • No shorts to power or ground
• Inspect the wiring harness for damage, chafing against belts/engine components, or exposed wires near the sensor or near moving parts.

C. Test the CMP sensor signal

• With ignition ON but engine OFF, back-probe the CMP sensor signal wire and measure the voltage signal when cranking or while cranking with the engine disconnected from fuel? A better test is:
  • While cranking (engine has to start), observe the CMP signal waveform. It should be a clean, periodic signal (pulses). If the signal is flat, erratic, or intermittent, the sensor or wiring is suspect.
• If you have an oscilloscope, observe the CMP waveform at idle and during slight throttle changes. A missing or irregular waveform suggests sensor or wiring issue.

D. Check the timing reference (mechanical timing check if indicated)

• If electrical checks pass but the symptom persists, consider timing-related causes:
  • Check for timing chain wear or misalignment (especially if a timing chain service was recently performed or if there are signs of timing issues such as a mechanical rattle or DTCs suggesting cam/crank sync problems).
  • Verify timing marks align per the Cruze service procedures; incorrect timing can cause cam signal anomalies and P0346.
• Note: This step often requires factory service information and specialized tools. If you’re not experienced with timing chains on this engine, seek professional help.

E. Cross-check with related sensors

• If the CMP signal appears weak or erratic, verify there is no issue with related sensors, such as the Crankshaft Position Sensor (CKP) circuit (P0335, P0336, etc.), since the ECM cross-checks cam and crank signals.
• Check for misfire-related codes (P0300-P0306) that could accompany P0346 due to timing or misfire conditions.

F. CMP sensor replacement trial (if electrical checks fail to show fault)

• If CMP sensor signal is inconsistent or the 5V/ground checks out but the issue persists, replace the CMP sensor with the correct part for your engine variant.
• After replacement, clear codes, start the engine, and recheck for any reoccurrence of P0346 and for improvement in running quality.
• Re-test with live data to confirm a stable CMP signal.

G. If P0346 persists after sensor replacement

• Re-check wiring and connectors again; sometimes a harness issue becomes more evident after a sensor swap.
• Consider PCM fault or need for reprogramming/updated calibration if a technical service bulletin or dealership update exists (not indicated in the provided data). In some cases, a software update can resolve sensor interpretation issues.

RELATED CODES

• P0340: Camshaft Position Sensor Circuit Malfunction (Bank 1 or generic if not bank-specified)
• P0341 / P0342: Camshaft Position Sensor Circuit Range/Performance (Bank 1) variants depending on engine configuration
• P0345–P0346 family variations related to camshaft position signal range/performance
• P0335 / P0336: Crankshaft Position Sensor Circuit issues (often checked when cam sensor issues are suspected)
• P0300–P0306: Random or specific misfire codes that may accompany cam timing or sensor issues
• P0016 / P0017: Crank/cam timing correlation (often seen if timing has actually shifted)

REPAIR OPTIONS AND COSTS (2025 prices)

Prices are estimates based on typical U.S. market ranges. Actual prices vary by region, labor rates, and whether OEM, aftermarket, or specialty parts are used.

• Camshaft Position Sensor (CMP) replacement

  • Parts: $25–$120 (sensor only; OEM vs aftermarket varies)
  • Labor: $60–$180
  • Total: approximately $85–$300

• CMP sensor wiring/connector repair or harness replacement

  • Parts: $0–$50 (simple connector repair) plus any harness segments if damaged
  • Labor: $100–$250 (depending on accessibility and extent of damage)
  • Total: roughly $100–$300+

• Timing chain/belt service (if timing is out of spec or chain wear is suspected)

  • Parts: $100–$350 (timing chain kit, guides, tensioners; varies by engine variant)
  • Labor: $500–$1,200
  • Total: roughly $600–$1,550
  • Note: This is a more significant repair and may be needed if there is actual timing deviation causing the CMP signal issues.

• Crankshaft/CMP sensor interaction problems requiring PCM replacement or reprogramming

  • PCM replacement (rare, typically after failures or software/ep update)
  • Parts: $250–$1,000
  • Labor: $100–$300
  • Total: $350–$1,300+
  • Software update or reprogramming: often handled by a dealer or specialized shop; cost varies.

• Optional/related service items if damage is found during diagnosis

  • Wiring harness replacement: $150–$400 parts + $100–$300 labor
  • Sensor cleaning or sealing (if contamination is the root cause and sensor is salvageable): minimal cost

DIY VS PROFESSIONAL

• DIY-friendly (CMP sensor replacement)

  • Pros: Low parts cost, can be a straightforward bolt-in sensor replacement on many Cruze engines.
  • Cons: Requires proper identification of the correct sensor for your engine variant, ability to disconnect and reconnect wiring safely, and some engines require removal of components to access the sensor. Improper reassembly can cause other issues.
  • Typical steps (high level): disconnect battery, locate CMP sensor, unplug connector, remove sensor, install new sensor with correct torque, reconnect, clear codes, test drive.

• Professional

  • Pros: Proper diagnosis (scoped waveform checks, harness testing, timing check, possible timing chain diagnosis) and correct sensor/engine handling with factory references and tools. Quicker turnaround for complex cases like timing chain concerns.
  • Cons: Higher initial cost due to labor.

• Tips if you DIY

  • Use a proper service manual for your exact engine, as oracles of the Cruze 2016–2019 can differ by engine code (1.4L turbo vs other variants).
  • Confirm the exact CMP sensor part number before purchasing.
  • Re-scan and clear codes after replacement; test under load to confirm resolution.

PREVENTION

• Regular maintenance
  • Change oil and filter at manufacturer intervals; ensure oil is clean and at proper level to avoid sensor contamination.
  • Use quality oil and avoid long oil-change intervals that could affect sensor performance indirectly (via oil contamination or sludge formation around sensors).
• Electrical system care
  • Periodically inspect wiring harnesses around the engine bay for signs of wear, moisture, or corrosion in connectors.
  • Use dielectric grease on sensor connectors during reassembly to improve corrosion resistance.
• Engine health monitoring
  • If you notice rough idle, misfires, poor acceleration, or the MIL comes on, diagnose early rather than continue driving. Prolonged issues can lead to more severe mechanical problems.
• Timing integrity
  • If your vehicle previously experienced timing-related service, ensure timing components are verified to spec when reassembling. Avoid reusing damaged components.

Data limitations and transparency

• The data you provided shows no complaints and no recalls in the NHTSA database for this specific issue with the Cruze (2016–2019). This guide is therefore based on general P0346 knowledge, Cruze engine layout basics, and typical diagnostic and repair practices. If you encounter a service bulletin (TSB) or dealership notice not reflected in the provided data, follow that guidance. The exact costs and procedures can vary by region, dealership, and engine variant (1.4L turbo vs others).
• If you’re not comfortable performing electrical tests, timing checks, or timing chain inspections, seek a qualified technician. In many cases, CMP sensor replacement can resolve P0346 when the CMP signal is out of range, but never assume timing issues are absent without proper checks.