P0340: Camshaft Position Sensor Circuit Malfunction
39 vehicles · 18 makes · $40-$8,000 repair
Most Reported On
P0340 is an OBD-II diagnostic trouble code meaning “Camshaft Position Sensor Circuit Malfunction.” This code means the engine computer lost or received an erratic signal from the camshaft position sensor. That sensor tells the computer the exact position and speed of the camshaft, which it uses together with the crankshaft sensor to time fuel injection and spark precisely. When the camshaft signal is missing, intermittent, or out of range, the computer sets P0340. Symptoms often include hard starting, stalling, rough running, or a no-start because the engine can't time itself correctly. This code is most commonly reported on 2001-2006 Acura MDX (Base, Touring), 2002-2009 GMC Envoy, and 2011-2017 Hyundai Elantra, plus 36 other vehicles, with repair costs ranging from $40 to $8,000.
Common Causes
Typical Repair Cost
Based on 50 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0340, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (39)
Timing Chain Guide and Cassette Failure on 4.0L SOHC V6
Timing Chain Cassette and Guide Failure on 4.0L SOHC V6
Camshaft Synchronizer Chirp and Oil Pump Drive Failure on 3.0L/4.0L V6
4.6L / 5.4L 2-Valve Triton Timing Chain Tensioner and Plastic Guide Rattle
4.0L SOHC Camshaft Position Sensor and Synchronizer Failure Causing P0340 Misfire and Stalling
Camshaft synchronizer chirp and failure (3.0L/4.0L OHV V6)
SHO V8 (Yamaha 3.4L) Camshaft Sprocket Failure
Camshaft synchronizer / CMP sensor bushing failure
Distributor internal oil seal failure contaminates crank/cam sensor, causing stalling and no-start
4.0L SOHC timing chain cassette, guide, and tensioner failure
5.4L Triton 3-Valve Cam Phaser / Timing Chain "Death Rattle"
Timing Chain Guide Wear and Chain Noise
Camshaft and Crankshaft Position Sensor Failure
Timing Chain Guide Wear / Chain Noise
Camshaft / Crankshaft Position Sensor Failure
Camshaft and Crankshaft Position Sensor Failure
Camshaft / Crankshaft Position Sensor Failure
Timing Chain / VVEL Rattle and Front Timing Cover Oil Leaks on VQ37VHR
Intermittent Engine Stalling While Driving
Crankshaft and Camshaft Position Sensor Failures Causing Stalling or No-Start
VQ35DE Timing Chain Stretch and Guide Wear
Crankshaft and Camshaft Position Sensor Failure Causing Intermittent Stall or No-Start
Distributor / Ignition System Failure Causing Sudden Stall or No-Start
Crankshaft Position Sensor Failure Causing Hot Stalling / No-Start
2.5L QR25DE Timing Chain Stretch and Tensioner/Guide Rattle
Crank/Cam Position Sensor Failure (No-Start, Random Stalling)
Optical distributor failure (VG30E/VG33E) causing misfire, rough idle, stalling and no-start
Optical crank/cam angle sensor failure inside the distributor (oil-seal leak) causing stalling and no-start
VQ35DE V6 Timing Chain Rattle from Worn Secondary Chain Guides and Tensioners
CAS (Crank Angle Sensor) Failure
FAQ
What does P0340 mean?
P0340 stands for "Camshaft Position Sensor Circuit Malfunction." This code means the engine computer lost or received an erratic signal from the camshaft position sensor. That sensor tells the computer the exact position and speed of the camshaft, which it uses together with the crankshaft sensor to time fuel injection and spark precisely. When the camshaft signal is missing, intermittent, or out of range, the computer sets P0340. Symptoms often include hard starting, stalling, rough running, or a no-start because the engine can't time itself correctly.
What are the most common causes of P0340?
The most common causes of P0340 are: Failed camshaft position sensor, Corroded or loose sensor connector, Damaged or shorted sensor wiring, Bad reluctor/tone ring on the camshaft, Loose timing chain/belt or jumped timing, Metal debris or oil contamination on the sensor tip, Poor sensor power or ground supply, Faulty PCM/ECM (rare). The specific cause varies by vehicle.
How much does it cost to fix P0340?
Repair costs for P0340 range from $40 to $8,000, depending on the vehicle and root cause.
Which vehicles are affected by P0340?
Au7o has documented P0340 across 39 vehicle models from 18 manufacturers: Acura, Chrysler, Dodge, Ford, GMC, Honda, Hyundai, Infiniti, Jeep, Kia, Mazda, Mitsubishi, Nissan, Opel, Ram, Renault, Saturn, Volvo.
Sources (12)
- ForumMDXers.org: Timing belt tensioner failure (P0300, P0301, P0302, P0303)
- ForumMDXers.org: DIY 01-06 Acura MDX Timing belt & waterpump Replacement tutorial
- mediaHow To Test The CKP Sensor 4.2L TrailBlazer Envoy
- media2002 GMC Envoy Crankshaft Position Sensor Problems - CarProblemZoo
- Forumcrankshaft sensor replacement - Trailvoy
- NHTSANHTSA complaints mentioning timing chain/engine noise on Infiniti FX45
- NHTSANHTSA complaints for Infiniti M35 involving camshaft/crankshaft sensor stalling
- NHTSANHTSA complaints mentioning timing chain / engine noise on Infiniti M56
- articleRenault 2TR engine specifications, oil, problems — MyMotorList
- ForumLooking at buying a Renault 2009 Koleos 2.5 petrol — timing chain — JustAnswer
- videoEricTheCarGuy - Volvo V40 Timing Belt Replacement Guide
- ForumCarComplaints - Kia Rio Timing Belt Problems
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.