P0340 on Hyundai: How to Diagnose & Fix
Camshaft Position Sensor Circuit Malfunction
1 Hyundai model · 2 documented issues · 1 critical · $150-$2,500 repair
P0340 on Hyundai by model: symptoms, diagnosis and fix
The crankshaft position sensor fails, causing intermittent stalling, hard starting, and no-start conditions. The problem often worsens when the engine is hot and may not trigger check engine codes initially. Sensor harness corrosion is a common contributing factor.
Common Symptoms
- Engine stalls randomly, especially at stop lights
- Hard starting or extended cranking time
- No-start condition for 5-10 minutes after stall
- Tachometer intermittently stops working
- Engine cuts out when hot
How to Fix
Replace crankshaft position sensor (use OEM part). Inspect and clean sensor connector for corrosion. Check wiring harness for breaks or shorts near engine block. Clear codes and test drive to verify repair.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Walker Products 235-1456 crankshaft position sensorOEMWalker Products 235-1456
aftermarket crankshaft-position sensor after signal/circuit diagnosis confirms replacement Fitment/availability: Walker catalog: 2011-2016 Elantra 1.8L and 2014-2017 Elantra 2.0L. Exclude the 2017 1.4L turbo and confirm engine/VIN/connec…
- Walker Products 235-1456 crankshaft position sensorOEMWalker Products 235-1456
Exclude the 2017 1.4L turbo and confirm engine/VIN/connector.
- Genuine Hyundai/Kia 39180-2B000 crankshaft position sensorOEMHyundai/Kia 39180-2B000
OE sensor path after diagnosis confirms the crank-sensor branch Fitment/availability: Cataloged Hyundai/Kia GDI/MPI applications including the relevant Elantra years; use VIN confirmation because 2011-2017 contains multiple engines and t…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Owner tips & cautions
- TipConsider OEM parts for critical components like sensors and electrical parts - aftermarket can be unreliable
- TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes
The 2.0L Beta engine in this generation relies on a timing belt service interval, and owner reports frequently describe belt breakage or stripped belt teeth causing sudden engine shutdown and, in many cases, internal valve damage. This is a well-known maintenance-sensitive failure on early-2000s Elantras, especially when the belt, tensioner, and idlers are overdue. Owners often report the engine cranking unusually fast afterward with little or no compression.
Common Symptoms
- sudden engine shutoff
- engine cranks but will not start
- fast cranking speed
- loss of compression
- slapping or chirping from timing cover area before failure
How to Fix
Verify timing belt age and mileage history immediately on any newly purchased Elantra from this era. If the belt has failed, perform a compression or leak-down test to check for bent valves before simply installing a new belt. Preventive service should include the timing belt, tensioner, idlers, and commonly the water pump and accessory belts at the same time.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Gates TCKWP284 timing-belt component kit with water pumpOEMGates TCKWP284
complete preventive timing-belt drive service after vehicle and production-date confirmation Fitment/availability: 1999-2005 Hyundai Elantra 2.0L and 2006 2.0L vehicles produced through October 30, 2006, as cataloged. Includes belt, tens…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Owner tips & cautions
- TipIf service history is unknown, treat the timing belt as overdue and replace it before daily driving the car.
- TipDo the water pump and cam/crank seals during timing belt service to avoid paying duplicate labor later.
Sources for this issue (1)
P0340 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0340 mean on a Hyundai?
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. On Hyundai it is documented across 1 model: Elantra.
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 on a Hyundai?
Published repair estimates on Hyundai range from $150 to $2,500 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0340 on a different make?
View P0340 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.