P0340 on 2023-2024 Acura Integra: Camshaft Sensor 'A' Circuit Malfunction Causes and Fixes

What's Unique About the 2023-2024 Acura Integra

The 2023-2024 Acura Integra uses the Honda L15CA 1.5L turbocharged engine, which is shared with the 11th generation Honda Civic Si. This engine has two camshaft position sensors: Sensor 'A' for the intake camshaft and Sensor 'B' for the exhaust camshaft. P0340 specifically refers to an issue with the intake ('A') sensor circuit. A notable real-world issue for this new platform has been rodents chewing through the soy-based wiring insulation used in modern engine bays, causing this exact code. A video of a 2024 Integra with P0340 showed the sensor's wiring harness completely chewed through.

Symptoms You May Notice

• Check Engine Light is on
• Engine is difficult to start or has an extended crank time
• Engine stalls or idles roughly
• Noticeable loss of engine power
• Engine cranks but will not start
• Reduced fuel economy
• Engine may enter a limited power "limp mode"

Most Likely Causes

1. Damaged wiring harness 🔴 High Probability A documented case on a 2024 Integra showed that rodents chewed through the sensor's wiring harness, causing a P0340 code. Modern cars, including the Integra, often use soy-based wire insulation that can attract vermin. 🎬 See how to protect your engine wiring from rodent damage. A Reddit user with a 2023 Integra reported a $1000 repair bill for rodent-chewed wiring.
   How to confirm: Visually inspect the entire wiring harness leading to the intake camshaft position sensor for any signs of chewing, fraying, or breaks. The damage may be obvious, as seen in videos of this specific car.
   Typical fix: Repair the damaged section of the wire. While Honda/Acura may recommend harness replacement, skilled repair by soldering and heat-shrinking the wires is often possible and much more cost-effective.
   Est. part cost: $5-$20 for wiring repair supplies
2. Failed Camshaft Position Sensor 'A' (Intake) 🔴 High Probability → Shop Engine Camshaft Position Sensor Sensors are electronic components that operate in a high-heat environment and can fail over time. This is a common failure point for this code across all makes.
   How to confirm: After confirming the wiring is intact, the easiest way to confirm a bad sensor is to replace it. A more advanced method involves using a multimeter to test for proper voltage and signal, or an oscilloscope to view the signal waveform. The intake sensor is easily accessible on top of the engine.
   Typical fix: Replace the Camshaft Position Sensor 'A' (Intake).
   Est. part cost: $60-$120
3. Poor connection at the sensor or PCM 🟡 Medium Probability
   How to confirm: Disconnect and inspect the electrical connector at the sensor and where it lands at the PCM. Look for corrosion, bent pins, or a loose fit. Re-seat the connection firmly.
   Typical fix: Clean the connector terminals with electrical contact cleaner and apply dielectric grease. If the connector itself is damaged, it will need to be replaced.
   Est. part cost: $0-$30

Rare But Worth Checking

• Stretched or jumped timing chain: → Shop Engine Timing Chain This is a serious mechanical issue. While rare on a new vehicle, if the code appears after other engine work or is accompanied by rattling noises, this should be investigated by a professional. A misalignment can cause the cam and crank signals to be out of sync, triggering the code.
• Faulty Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is extremely rare and should only be considered after all other possibilities (sensor, wiring, mechanical timing) have been exhaustively ruled out. A forum user with a wrecked 2023 Integra reported multiple codes including P0340 after the PCM connector was hooked up backwards, indicating a potential PCM failure.
• Damaged reluctor wheel: The sensor reads teeth on a reluctor wheel on the camshaft. If this wheel is damaged or has missing teeth, it can cause an inconsistent signal and trigger P0340. This is very unlikely without other major engine trauma.

Diagnosis Steps

1. Read the code with an OBD-II scanner to confirm P0340 is present.
2. Locate the Camshaft Position Sensor 'A' (Intake). On the L15CA engine, it is on the top of the valve cover, closer to the air intake manifold.
3. Perform a detailed visual inspection of the sensor and its wiring harness. Look for any signs of damage, especially from rodents, which is a known issue.
4. Check the electrical connector for a secure fit, corrosion, or damaged pins. Unplug, inspect, and re-seat it.
5. If wiring looks good, the most common and straightforward next step for a DIYer is to replace the sensor. It is held in by a single 10mm bolt.
🎬 Watch this walkthrough on how to replace the camshaft sensors.
6. If the problem persists after replacing the sensor, the wiring circuit needs to be tested for continuity, shorts, and proper voltage from the PCM. This requires a multimeter and a wiring diagram.
7. If the circuit and sensor are confirmed good, investigate potential mechanical issues like timing chain alignment, although this is rare on a new vehicle without other symptoms like engine noise.

Parts You'll Likely Need

• Engine Camshaft Position Sensor (OEM #37510-59B-J01) — This is the sensor that measures the intake camshaft's position. Failure of the sensor itself is a primary cause of the P0340 code. This part number fits a wide range of modern Honda/Acura vehicles.
  Trusted brands: Acura (OEM), Honda (OEM), Delphi, NTK/NGK
  OEM price range: $60-$120
  Aftermarket price range: $30-$70

Related Codes That Often Appear With This One

• P0341 (Camshaft Position Sensor 'A' Circuit Range/Performance)
• P0335 (Crankshaft Position Sensor 'A' Circuit Malfunction)
• P0016 (Crank/Camshaft Position Correlation)

Mechanic-Grade Diagnostic Values

• CMP Sensor 5V Reference Supply — expected: 4.8V to 5.2V. Failure: 0V or significantly lower indicates an open/short in the supply circuit or a PCM fault.
• CMP Sensor Ground Circuit Resistance — expected: Below 3.0 Ohms. Failure: High or infinite resistance (OL) indicates an open or corroded ground circuit.
• CMP Sensor Signal Wire Voltage (Key On, Engine Off) — expected: Approx. 4.8V to 5.0V. Failure: 0V or low voltage suggests a problem with the sensor or wiring.
• CMP Sensor Signal Test (Manual) — expected: Voltage should drop from ~5V to ~0V when a piece of metal is passed in front of the sensor tip.. Failure: Voltage does not change, indicating a faulty sensor.

Scan Tool Commands That Help

• Honda Diagnostic System (HDS): CRANK PATTERN LEARNING — After replacing a camshaft or crankshaft sensor, or after timing components have been serviced, to ensure the PCM correctly learns the new sensor patterns and their correlation. Failure to do this can sometimes cause persistent correlation codes.

Wiring & Ground Locations

• G101 — Typically found on the engine block or cylinder head, often near the thermostat housing or a main coolant outlet, grounding the engine harness to the chassis.. This is a primary ground point for the engine's sensors. A loose or corroded G101 ground can create a floating ground, causing erratic voltage readings for many sensors, including the camshaft position sensor, leading to a P0340 code.
• CMP Sensor Connector — On the intake camshaft position sensor, located on top of the valve cover.. This 3-pin connector provides the sensor with power, ground, and a path for the signal to return to the PCM. Testing for 5V reference, good ground, and a 0-5V signal happens at these pins.

Real Owner Repair Stories

• Honda-Tech forum user (Acura RSX (similar Honda K-series engine principle)) — Engine would crank but not start, P0340 code present.
  ❌ Tried (didn't work) Initial diagnosis pointed towards a bad sensor or wiring.
  ✅ What actually fixed it The code appeared immediately after a timing chain replacement. The root cause was that the mechanical timing was off. Re-timing the engine correctly resolved the P0340 code and the no-start condition.

Diagnostic Flowchart

Other Known Issues on This Vehicle

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

• Sticky or Notchy Steering at Highway Speeds 🔴 High — Widespread issue affecting 2023-2024 Integras and platform mates. A recall (24V-744) and TSB (23-037) have been issued. (Ref: TSB 23-037 / NHTSA Recall 24V-744)
• Infotainment System Glitches & CarPlay/Android Auto Drops 🟠 Medium — Frequently reported by owners. Issues include screen freezing, random disconnects of wireless CarPlay/Android Auto, and slow response.
• Interior Rattles 🟡 Low — Common owner complaint, often from door pillars, sunglasses holder, or dashboard areas.
• CVT Hesitation or 'Rubber Band' Effect 🟠 Medium — Some owners of CVT-equipped models report a noticeable delay when accelerating from a stop.
• Driver Seat Memory/Mirror Tilt Malfunction 🟡 Low — Some owners report the driver's seat memory fails to return to the set position and the passenger mirror does not return to its original position after reversing.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used wiring harness pigtail from a salvage yard is a smart and cost-effective choice if your original connector or wiring was destroyed by rodents. It provides an OEM-quality connector and wire colors for a proper repair.

Donor-vehicle mileage cap: roughly under 50000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For a wiring pigtail, ensure the plastic connector is not brittle and the locking tab clicks securely.
• Inspect the wire insulation for any cracks or signs of heat damage.
• Check the metal pins inside the connector for any green or white corrosion.

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

• Engine Camshaft Position Sensor

Aftermarket brands forum-validated for this vehicle:

• NTK/NGK
• Delphi

Brands owners have reported issues with on this vehicle:

• Avoid unbranded, 'white-box' sensors from online marketplaces. While cheap, they have a high failure rate and can cause difficult-to-diagnose drivability issues, wasting time and money.

Real Owner Stories

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

Related OBD-II Codes

• P0657 — Actuator supply voltage 'A' circuit/open; appeared alongside P0340 in cases involving PCM connector damage.
• P0443 — Evap system purge control valve 'A' circuit; noted as a companion code when the PCM or its wiring is compromised.
• P0088 — Fuel rail/system pressure-too high; observed with P0340 during electrical faults involving the PCM.
• P0123 — Throttle/pedal position sensor/switch 'A' circuit high; reported in conjunction with P0340 when major wiring or PCM issues occur.

Frequently Asked Questions