engine
Crankshaft Position Sensor
for 2021 Hyundai Tucson 2.5L I4 · AWD
Difficulty
Easy
Time
1.0 h
Tools
7
Steps
10
This procedure covers the removal and installation of the crankshaft position sensor on a 2016-2024 Hyundai Tucson with the 2.5L I4 AWD engine.
Warnings
⚠Allow engine to cool completely before beginning work. Components near the crankshaft position sensor can retain heat.
ℹ️Disconnecting the battery will erase radio presets and may require window auto-up/down recalibration.
⚠Do not drop the sensor bolt into the engine bay. Use a magnetic pickup tool if necessary.
Tools required
10mm socketEssential
Ratchet and extensionEssential
Torque wrench (5-30 Nm range)Essential
Plastic pry tool
Shop towelsEssential
Wire brush or electrical contact cleaner
Dielectric grease
Parts
- Crankshaft Position Sensor × 1 — Use OEM specification (Hyundai 39180-2E300 or equivalent)
- Sensor O-ring (if not included with sensor) × 1 — Use OEM specification
Preparation
- Park vehicle on level ground and engage parking brake
- Allow engine to cool completely (minimum 30 minutes after running)
- Open hood and secure in raised position
- Disconnect negative battery terminal and wait 3 minutes before proceeding
- Locate the crankshaft position sensor on the lower front of the engine block, near the crankshaft pulley on the driver's side
Procedure
- 1Access the crankshaft position sensorFrom above the engine, identify the electrical connector for the crankshaft position sensor. You may need to trace the wiring harness from the sensor location. Remove any plastic engine covers if they obstruct access using appropriate fastener removal.
- 2Disconnect the electrical connectorPress the locking tab on the crankshaft position sensor electrical connector and carefully pull the connector straight off the sensor. Do not pull on the wires themselves. If the connector is tight, use a plastic pry tool to gently release it.
- 3Remove the sensor mounting boltUsing a 10mm socket with extension and ratchet, remove the single bolt securing the crankshaft position sensor to the engine block. Keep track of this bolt as it is small and can easily be lost. The sensor is located on the timing chain cover area near the crankshaft pulley.Torque specCrankshaft Position Sensor10 Nm (7 lb-ft)
- 4Extract the sensorCarefully pull the crankshaft position sensor straight out from the engine block. It may require a gentle twisting motion to break it free. Be careful not to damage the sensor tip or mounting hole. Remove the O-ring seal from the sensor or mounting hole if it remains in place.
- 5Clean the mounting areaUse shop towels to clean the sensor mounting hole in the engine block. Remove any debris, old gasket material, or oil buildup. Inspect the mounting hole for damage or excessive wear. If available, use electrical contact cleaner to ensure the area is completely clean and dry.
- 6Inspect and prepare the new sensorVerify the new crankshaft position sensor matches the old unit in connector style and physical dimensions. Check that the O-ring is properly seated on the new sensor. If the O-ring is separate, install it onto the sensor body. Optionally apply a thin coat of dielectric grease to the electrical connector to prevent corrosion.
- 7Install the new sensorCarefully insert the new crankshaft position sensor into the mounting hole in the engine block, ensuring the O-ring does not get pinched or displaced. Push the sensor in until it is fully seated against the mounting surface. The sensor should sit flush with minimal gap.
- 8Install and torque the mounting boltThread the sensor mounting bolt by hand to avoid cross-threading. Once hand-tight, use a torque wrench to tighten the bolt to specification. Do not overtighten as this can crack the sensor housing or damage the threads in the aluminum engine block.Torque specCrankshaft Position Sensor10 Nm (7 lb-ft)
- 9Reconnect the electrical connectorPush the electrical connector firmly onto the new crankshaft position sensor until you hear or feel a positive click indicating the locking tab has engaged. Gently tug on the connector to verify it is secure and will not pull off.
- 10Reconnect the batteryReconnect the negative battery terminal and tighten securely. Reinstall any engine covers that were removed during disassembly.
Reassembly
- Ensure all electrical connections are secure and properly routed away from moving parts
- Verify no tools or parts were left in the engine bay
- Double-check that the sensor mounting bolt is torqued to specification
Verification
- Turn the ignition to the ON position (do not start) and verify no warning lights related to engine sensors are illuminated on the dashboard
- Start the engine and confirm it starts normally without extended cranking
- Allow the engine to idle and verify smooth operation with no rough idle or stalling
- Use an OBD-II scanner to verify no crankshaft position sensor codes (P0335, P0336, P0337, P0338, P0339) are present
- If equipped, verify the tachometer is reading correctly during idle
- Test drive the vehicle briefly to confirm normal acceleration and no check engine light