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Does your Hyundai or Kia stall pulling away from a light, then crank strong and refuse to fire until it cools? A dying camshaft sensor is the usual cause. The fix is this camshaft position sensor for the Hyundai Elantra, Tucson, Kia Forte, and Soul — one bolt, one connector, fifteen minutes.

What the cam signal does

The camshaft position sensor is a small Hall-effect switch — a powered sensor that flips as a tooth on the cam passes. The ECM — the car's main computer — reads it to fire each injector and coil in order.

The crank sensor tells the ECM how fast the engine spins, but not which stroke each piston is on. The cam signal closes that gap:

• The same crank position looks identical on the compression and exhaust strokes.
• The cam turns at half crank speed, so its signal marks the firing stroke.
• Lose it and the ECM has nothing to time injection against — the engine stalls, then cranks without firing.

P0340, P0341, and the crank-side P0335

Start with the code; each names a different fault. (DTC = diagnostic trouble code, the label the ECM stores when a check fails.)

• P0340 — "Camshaft Position Sensor A Circuit." The cam input is dead: a quit sensor, a corroded plug, or a broken wire.
• P0341 — "Camshaft Position Sensor A Circuit Range/Performance." The signal arrives but makes no sense. That points at heat drift, an oil-fouled face, or a cam moved out of time.
• P0335 — "Crankshaft Position Sensor A Circuit." The same family on the crank side. It convicts the crank sensor, not the cam sensor.

Only the cam code showing? Replace the sensor. Both codes together usually mean a shared power or ground problem, or a jumped belt or chain.

Crank code alone? Replace that sensor. Gamma 1.6L and Nu 2.0L engines take the 39180-2B000 crank sensor for the Veloster, Elantra, and Accent; the 2.4L Tucson, Sonata, and Sorento take the 39180-2G000 crank sensor for Hyundai and Kia.

One sensor, a family of numbers

Every number below is a three-pin Hall-effect cam sensor in the same housing family. What separates them is engine generation. Order by VIN, not looks.

The 39350-2E200 and the 39350-23700 look alike but serve two decades of the same engine, so confirm fitment by VIN. Running two of these cars? The two-pack of 39350-2E200 sensors for the 2016-2022 Elantra covers the second car for less than one genuine unit.

The failure pattern: stalls hot, restarts cool, then no-start

Heat turns an intermittent sensor into a breakdown. As the engine bay soaks, the sensor's threshold drifts and the signal drops out. The engine stalls.

Park it for twenty minutes and it starts again. That is the "dies hot, restarts cold" signature. Left alone the drift becomes permanent.

• Between episodes you feel hesitation off idle, or a stumble at steady cruise.
• Warm starts take longer to catch than cold ones.
• These overlap with ignition faults — the guide to diagnosing common ignition coil issues splits a load-related misfire from a fault that follows temperature.

A scan tool settles it. Cam sync dropping out while the engine stumbles means sensor; moving misfire counters mean ignition.

Finding it and swapping it

The sensor sits on the cylinder head, held by one bolt, with a three-pin connector and an O-ring seat. No fluid drains and no relearn is needed:

1. Unclip the three-pin connector.
2. Back out the single bolt.
3. Twist the sensor free of its bore.
4. Fit the new unit and reverse the steps.

Ten to fifteen minutes with a socket and flat screwdriver. Two checks make the repair stick:

• Check the connector for oil. These valve cover gaskets weep, and oil in the pins makes a P0341 no sensor will fix.
• Look at the old sensor's face. An oily film delays the signal edges — that film alone can be the fault.

Which number to order is a generation question, not a quality one: old 2.0L DOHC cars take the 39350-23700 family, Nu 2.0L cars the 39350-2E200, Theta cars the CMP3052.

The sensors sit with their wiring and crank partners in the auto electronics collection. Gaskets and timing hardware sit in the engines and engine parts collection.

When the code is real but the sensor is innocent

P0341 is a correlation code, so the sensor is not always the part at fault:

• A stretched timing belt or worn chain lets the cam lag the crank, and the sensor reports exactly what it sees. The timing belt and water pump guide for the 2.0L, 2006-2012 covers the belt-side checks.
• A worn cam phaser or a lazy oil-control valve moves phasing on the VVT engines. The camshaft timing solenoid guide walks the same reasoning on a GM platform.
• Wiring shuts the signal off too: a corroded splice, a chafed harness, or a bad ground posts a P0340 that comes back on the new part.

The code definitions and three-wire logic are generic. The Ford camshaft position sensor guide shows the same P0340/P0341 structure on another engine family.

Frequently asked questions