Vehicle Sensors
Your vehicle relies on sensors to keep it safe and running smoothly. Learn which car sensors are critical to repair immediately, what they do, and how sensor failure can affect your car’s performance.
Vehicle Sensors Explained — Which Ones Are Critical, and What They Do
Modern vehicles are packed with electronic sensors designed to improve performance, fuel economy, emissions, and safety. But what happens when one of these sensors fails? Some can shut your vehicle down or damage the engine, while others are less urgent. Here’s a breakdown of the most critical sensors and the ones that can be temporarily ignored (with caution).
Critical Sensors — Fix These ASAP
1. Oxygen Sensor (O2)
- Purpose: Monitors oxygen levels in exhaust gases to manage fuel injection.
- Failure Effects: Poor fuel economy, engine misfires, increased emissions.
- Warning Signs: Check engine light, rough idling, failed emissions test.
2. Mass Air Flow Sensor (MAF)
- Purpose: Measures the air entering the engine to balance fuel mixture.
- Failure Effects: Engine hesitation, stalling, poor fuel efficiency.
- Warning Signs: Loss of power, hard starting, check engine light.
3. Crankshaft Position Sensor
- Purpose: Tracks engine speed and piston position for ignition timing.
- Failure Effects: Car may not start, stalling, rough engine operation.
- Warning Signs: Random misfires, engine won’t turn over.
4. Camshaft Position Sensor
- Purpose: Works with the crankshaft sensor to control valve timing.
- Failure Effects: Engine won’t start or run smoothly.
- Warning Signs: Poor acceleration, engine surging.
5. Coolant Temperature Sensor
- Purpose: Tells the ECU how hot the engine is.
- Failure Effects: Overheating or incorrect fuel mixture.
- Warning Signs: Temperature gauge stuck, overheating engine.
6. ABS Wheel Speed Sensor
- Purpose: Monitors wheel speed for the ABS and traction control systems.
- Failure Effects: Loss of ABS and traction control.
- Warning Signs: ABS warning light, sliding under braking.
Non-Critical – But Still Important Sensors
1. Ambient Air Temperature Sensor
- Purpose: Adjusts climate control or engine mixture based on outside air temp.
- Failure Effects: Poor climate control accuracy.
- Warning Signs: Inaccurate outside temp reading.
2. Fuel Temperature Sensor
- Purpose: Helps the ECU adjust fuel mixture based on fuel temperature.
- Failure Effects: Slight fuel efficiency drop.
- Warning Signs: Rarely triggers warnings.
3. Rain Sensor (for Auto Wipers)
- Purpose: Automatically turns on wipers in rain.
- Failure Effects: Manual wiper activation only.
- Warning Signs: Wipers don’t auto-start.
4. Parking Sensor / Ultrasonic Sensors
- Purpose: Assists with parking and obstacle detection.
- Failure Effects: Reduced convenience or risk of minor collisions.
- Warning Signs: Parking alert failure message.
🛠️ How to Tell If a Vehicle Sensor Has Failed
Check engine light (CEL) is the most common indicator.
Sudden changes in performance, fuel usage, or idle quality.
Use a diagnostic scanner to read OBD2 fault codes.
Don’t Ignore Sensor Warnings!
If your check engine light is on or your car is running poorly, your sensors could be to blame.
👉 Book a diagnostic test at your nearest e-CAR workshop today — we’ll scan your car, identify the faulty sensor, and fix it fast.
📞 Call us at 086 000 3227 or find your nearest branch now.
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