P0340 on 2016-2020 Kia Sorento 3.3L V6: Camshaft Sensor Causes and Fixes

What's Unique About the 2016-2020 Kia Sorento

On the Lambda II 3.3L V6 engine, the four camshaft position sensors (intake/exhaust for each bank) are often identical and interchangeable. This allows for a simple diagnostic trick: swapping the suspected bad sensor from the less accessible rear bank (Bank 1) with the easily accessible sensor on the front bank (Bank 2). If the fault code follows the sensor and changes to P0345, you've confirmed the sensor is the problem before spending any money on parts.

Symptoms You May Notice

• Check Engine Light is on
• Engine is difficult to start or cranks but won't start
• Engine stalls, sometimes while driving
• Rough or unstable idle
• Noticeable loss of engine power and acceleration
• Reduced fuel economy
• Engine may be hard to start when hot, but starts normally when cool.

Most Likely Causes

1. Failed Camshaft Position Sensor (Bank 1 Intake) 🔴 High Probability → Shop Engine Camshaft Position Sensor These Hall effect sensors can weaken or fail electronically over time. It is the most common point of failure for this code. Owner experiences suggest that using genuine OEM sensors is highly recommended, as some have reported that aftermarket sensors did not fix the issue or failed prematurely.
   How to confirm: Swap the Bank 1 intake sensor (rear bank) with the Bank 2 intake sensor (front bank). Clear the codes and run the engine. If the code changes to P0345 (Camshaft Position Sensor 'A' Circuit Bank 2), the sensor is faulty.
   Typical fix: Replace the faulty camshaft position sensor. The sensor for Bank 1 Intake is on the rear valve cover. 🎬 Watch: How to locate and remove the exhaust camshaft sensor.
   Est. part cost: $30-$120
2. Wiring Harness or Connector Issue 🟡 Medium Probability The engine bay environment can cause wiring to become brittle or connectors to corrode. The wiring for the rear sensor is in a tighter space and could be subject to chafing. In some reported cases, the fix was as simple as cleaning the connector pins with electrical contact cleaner and ensuring it was securely reconnected.
   How to confirm: Visually inspect the wiring harness and connector for the Bank 1 intake camshaft sensor. Check for frayed wires, loose pins, or corrosion. Use a multimeter to test for 5V reference, ground, and a signal back to the PCM.
   Typical fix: Repair the damaged section of wiring or replace the connector pigtail. Always try cleaning the connector first.
   Est. part cost: $10-$40
3. Blown Sensor Fuse ⚪ Low Probability The camshaft position sensors are often on a shared fuse with other sensors. A short in another component could blow the fuse, cutting power to the cam sensor.
   How to confirm: Check the fuse box in the engine compartment for a fuse labeled 'SNSR' or 'SENSOR'. On some Kia models, it may be labeled 'SNSR3' and is a 10 amp fuse. Visually inspect the fuse and test for continuity.
   Typical fix: Replace the blown fuse. If it blows again, further diagnosis is needed to find the short circuit.
   Est. part cost: $1-$5

Rare But Worth Checking

• Stretched Timing Chain or CVVT System Fault: → Shop Engine Timing Chain This is a more serious mechanical issue. It will typically be accompanied by other codes related to cam/crank correlation (like P0016) or timing over-advanced/retarded (like P0011, P0014). A known, though uncommon, mechanical failure is the dowel pin on the CVVT phaser shearing or sinking into the camshaft, allowing the phaser to rotate independently and lose timing, which can trigger P0340.
• Failed Crankshaft Position Sensor: → Shop Engine Crankshaft Position Sensor A failing crankshaft sensor can sometimes cause erratic signals that the PCM misinterprets as a camshaft sensor fault. There are owner reports of a P0340 code with a 'no start when hot' symptom being resolved by replacing the crankshaft position sensor, as its failure can send confusing signals to the PCM.
• Failed Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is extremely rare. The PCM should only be considered after all other possibilities (sensor, wiring, mechanical timing) have been exhaustively ruled out by a professional.

Diagnosis Steps

1. Read all fault codes stored in the PCM. Note any other codes besides P0340.
2. Turn the engine off. Remove the plastic engine cover.
3. Locate the Bank 1 (rear) intake camshaft position sensor. Visually inspect its electrical connector and nearby wiring for any signs of damage, melting, or corrosion. Try cleaning the connector with electrical contact cleaner as a first step.
4. For a definitive test, swap the Bank 1 intake sensor with the identical Bank 2 intake sensor on the front valve cover. They are held by a single 10mm bolt.
🎬 Watch: Step-by-step walkthrough for changing Sorento camshaft sensors.
5. Clear all fault codes with a scanner, start the engine, and let it run for a minute.
6. Re-scan for codes. If P0345 now appears, the sensor you moved is faulty and needs to be replaced. It is highly recommended to use a genuine OEM part.
7. If P0340 returns, the issue is in the wiring or circuit for Bank 1. Use a multimeter to check for a 5-volt reference and a good ground at the connector with the key on, engine off.
8. If the wiring and fuse are confirmed to be good but the code persists, the problem may be mechanical (timing chain, CVVT phaser) and requires professional diagnosis.

Parts You'll Likely Need

• Camshaft Position Sensor (OEM #39318-3L000) — This is the most common component to fail and trigger a P0340 code. The sensors on the 3.3L V6 are interchangeable, but this is the primary number for the application. Owner forums strongly suggest using OEM/Genuine parts to avoid repeat failures.
  Trusted brands: Kia (Genuine OEM), Hyundai (Mobis), Delphi, NTK/NGK, Beck/Arnley
  OEM price range: $70-$120
  Aftermarket price range: $30-$75

Related Codes That Often Appear With This One

• P0345 — Camshaft Position Sensor 'A' Circuit (Bank 2). This code will appear after swapping a faulty Bank 1 sensor to Bank 2 for diagnostic purposes.
• P0335 — Crankshaft Position Sensor 'A' Circuit. A problem with the crankshaft sensor can sometimes lead to timing confusion and trigger a camshaft sensor code.
• P0011 — 'A' Camshaft Position - Timing Over-Advanced (Bank 1). This suggests a mechanical timing problem with the CVVT system or timing chain, which is a deeper issue than just a sensor circuit fault.

Technical Service Bulletins (TSBs) & Recalls

• TSB ENG253 / WTY035: Warranty extension for 15 years/180,000 miles on 2016-2017 3.3L models for coolant leaks from the cylinder head gasket area.

Platform-Specific Known Issues

• While no TSBs are directly linked to P0340, Kia issued TSB ENG253 (extending the warranty via WTY035) for 2016-2017 Sorento 3.3L models for potential cylinder head gasket coolant leaks, which can cause overheating and misfires.
• Kia also issued a recall (SC153 / NHTSA 17V-586) for some Sorentos due to improperly heat-treated crankshafts that could fail and cause an engine stall. While a different root cause, it highlights the potential for engine stalling on this platform.

Mechanic-Grade Diagnostic Values

• Camshaft Position Sensor Connector Pin 1 (Power) — expected: ~5.0V DC with key on, engine off. Failure: 0V or significantly lower than 5.0V indicates a power supply issue (e.g., blown fuse, wiring fault).
• Camshaft Position Sensor Connector Pin 2 (Ground) — expected: Near 0V DC / Good continuity to chassis ground. Failure: Voltage present or high resistance to ground indicates a bad ground connection.
• Camshaft Position Sensor Connector Pin 3 (Signal) — expected: A square wave signal switching between 0V and 5V as the engine is cranked (requires oscilloscope). A multimeter may show an average voltage.. Failure: No signal, or a signal that is stuck high or low, indicates a failed sensor or a break in the signal wire.
• Sensor Power Fuse ('SNSR3') — expected: 10 Amps, continuity across the fuse terminals. Failure: Blown fuse (no continuity) will cut power to the sensor circuit.

Scan Tool Commands That Help

• Kia GDS / Advanced Scanners (Autel, etc.): Cam/Crank Relearn or Crank Angle Sensor Error Relearn — This function is used to synchronize the PCM's learned values for the camshaft and crankshaft positions. However, for the 2017 Sorento, the factory service manual does not require this procedure for a simple sensor replacement. It is typically only necessary after major mechanical work like a timing chain or phaser replacement.

Wiring & Ground Locations

• CMP Sensor Connector — On the sensor body, plugged into the engine wiring harness. Bank 1 is the rear bank, closer to the firewall.. This 3-pin connector provides power, ground, and the signal path for the sensor. Corrosion or damage here is a common cause of the P0340 code. The three pins are for 5V power, ground, and the 5V pulse signal.

Real Owner Repair Stories

• NHTSA ODI #11711571 — An owner reported their vehicle was showing multiple fault codes simultaneously, specifically P0340, P0365, P0780, and P0010.
• Reddit user comment in r/kia (Kia Sorento (year not specified, but with Lambda 3.3L V6)) — Camshaft sensor code (implies P0340 or similar).
  ❌ Tried (didn't work) Took vehicle to the dealership.
  ✅ What actually fixed it The user was advised by the dealership that the entire engine needed replacement. However, a commenter (a likely technician) stated the common, real-world cause is the dowel pin for the CVVT sprocket sinking into the camshaft, allowing the sprocket to spin independently and throw off timing. The fix is to replace the camshaft and CVVT phaser, a repair that can be done without removing the timing cover.
• Reddit user post in r/MechanicAdvice (Nissan Sentra (concept applies universally)) — Car stalled, then restarted fine. Check engine light with code P0340.
  ❌ Tried (didn't work) Replacing the camshaft position sensor with a new aftermarket (Hitachi) part.
  ✅ What actually fixed it The check engine light and stored P0340 code did not disappear automatically after replacing the part. The final fix was to manually clear the fault codes from the PCM using an OBD-II scanner. After clearing, the code did not return, confirming the new sensor had fixed the issue.

When the Usual Fixes Don't Work

• In a documented case on a similar Lambda V6, a P0018 code (Cam/Crank Correlation) persisted after multiple sensor replacements. The ultimate cause was found to be a sheared dowel pin on the CVVT cam phaser, which was caused by a low oil condition. This highlights that even when a code points to a sensor circuit, the root cause can be a severe mechanical failure that a new sensor will not fix.

OEM Part Supersession History

• 39318-3L000 → 39318-3L000 (current) — This is the primary part number for the 2016-2020 3.3L V6.
  Heads up: An older part, 39318-3L100, was used on earlier Lambda engines (approx. 2006-2011) and should not be used on this engine. Part number 39318-3C500 is also cited as an interchangeable number for 39318-3L000.

Model Year Variations Within This Range

• 2017-2020: Starting with the 2017 model year for some 3.3L V6 applications (like the Cadenza), Kia integrated the Barometric Pressure Sensor (BPS) into the main Engine Control Module (ECM/PCM). The 2016 Sorento used an external BPS. While not directly part of the P0340 circuit, a failing internal BPS on later models could theoretically affect engine load and timing calculations in a way that might contribute to or complicate timing-related diagnoses.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• GDI Intake Valve Carbon Buildup 🟠 Medium — Common to all GDI engines, including the Lambda II 3.3L. Becomes noticeable after 60,000-100,000 miles, causing rough idle, hesitation, or misfire codes.
• Engine Oil Consumption 🟠 Medium — Some owners report noticeable oil consumption between changes. Low oil levels can cause a variety of timing-related fault codes, including those for the CVVT system. Owners should check oil levels regularly.
• Cylinder Head Gasket Coolant Leak 🔴 High — Affects 2016-2017 Sorento 3.3L models specifically. Can cause overheating, coolant loss, or misfires. (Ref: TSB ENG253 / Warranty Extension WTY035)

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used part is generally not recommended for this repair. However, if the failure is confirmed to be the wiring connector (pigtail) and not the sensor itself, sourcing a used pigtail from a junkyard vehicle is a cost-effective and reliable solution.

Donor-vehicle mileage cap: roughly under 150000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For a wiring pigtail: ensure the plastic is not brittle or cracked.
• Check that the connector's locking tab is intact and functional.
• Inspect the pins inside the connector for any signs of green or white corrosion.
• Ensure there is at least 4-6 inches of wire attached to allow for proper splicing.

OEM-only on this vehicle (don't cheap out):

• Camshaft Position Sensor: Forum and owner experiences strongly indicate that aftermarket sensors have a high rate of being faulty out-of-the-box or failing prematurely, leading to a repeat of the P0340 code.
• CVVT Cam Phaser: If this more serious mechanical part is the cause, using an OEM replacement is critical for ensuring correct engine timing and longevity.

Aftermarket brands forum-validated for this vehicle:

• NTK/NGK
• Delphi
• Beck/Arnley

Brands owners have reported issues with on this vehicle:

• Unbranded 'white box' sensors or low-cost store brands are frequently reported to cause issues.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0345 — This is the code for Camshaft Position Sensor 'A' Circuit Bank 2. It is used during diagnosis; if you swap the Bank 1 and Bank 2 sensors and the code moves from P0340 to P0345, the sensor is confirmed faulty.
• P0300 — Random or multiple cylinder misfires can occur alongside P0340 due to incorrect ignition timing or as a result of the cylinder head gasket leaks mentioned in TSB ENG253.
• P0011 — Often associated with CVVT system issues or low oil levels, which are known to affect the Lambda II engine and can appear with camshaft circuit codes.
• P0014 — Related to camshaft timing over-advanced; may trigger if the mechanical timing (CVVT phaser or dowel pin) has failed, a condition sometimes confused with a simple P0340 sensor failure.

Frequently Asked Questions