Why Sensors Are the New Weak Point in Cars

Modern vehicles are smarter than ever. They monitor everything—from engine performance to tire pressure—using a complex network of car sensors that help the engine control unit manage optimal engine performance.

But here’s the catch.

While engines and gearboxes have become more reliable, faulty car sensors are quickly becoming the most common failure point we see—especially on Irish roads.

What Do Car Sensors Actually Do?

Today’s cars rely on dozens of key sensors working together.

They monitor things like:

• Camshaft position sensor and crankshaft position sensor for ignition timing and fuel injection control, critical for the ignition process and optimal combustion
• Throttle valve position with the throttle position sensor (TPS), which informs the engine control module (ECM) or engine control unit (ECU) to adjust fuel injection rates for optimal engine performance
• Wheel speed with the vehicle speed sensor
• Exhaust gases through the oxygen (O2) sensor, helping regulate exhaust gases and maintain emissions compliance by optimizing the air fuel ratio
• Airflow and air fuel mixture using the mass airflow (MAF) sensor and manifold absolute pressure (MAP) sensors, essential for adjusting fuel injection and ignition timing to maintain the correct fuel ratio
• Engine temperature via the coolant temperature sensor, crucial for managing the cooling system and ensuring the combustion process runs smoothly in the combustion chamber

All of this data feeds into the engine control unit (ECU), sometimes called the engine control module (ECM), which adjusts how the car runs in real time for optimal vehicle performance and fuel efficiency.

Understanding how car sensors work is key to diagnosing issues early. When a malfunctioning sensor sends incorrect data, it can cause all sorts of problems—from poor acceleration and engine hesitation to increased fuel consumption and costly repairs.

Why Sensors Fail More Often Now

The biggest reason is simple: there are more sensors involved.

Modern vehicles—including Suzuki models like the Vitara, Swift, and S-Cross—are packed with advanced sensors to improve:

• Safety systems
• Emissions (important for NCT)
• Fuel efficiency

In our experience, more electronics mean more small components that can wear out over time, especially sensors involved in monitoring air pressure, fuel pressure, and ignition timing.

Irish Conditions Don’t Help

Ireland’s climate plays a bigger role than most drivers realise.

Think about it:

• Short trips around Dublin preventing optimal operation of sensors and engine components
• Cold starts in winter affecting sensor responsiveness and combustion process
• Constant moisture and rain leading to corrosion and sensor malfunctions

We often see sensor issues linked to dampness, loose connections, clogged air filters affecting the malfunctioning MAF sensor, or repeated short journeys where the car never fully warms up, impacting engine efficiency and causing sensor malfunctions.

Common Sensor Problems We See

At Gerry Caffrey Motors, certain car sensor problems come up again and again.

These include:

• Parking sensor glitches
• ABS wheel speed sensor faults affecting safety systems
• Crankshaft and camshaft position sensor failures resulting in ignition timing issues and no-start conditions
• Throttle position sensor (TPS) faults causing engine hesitation and poor engine performance
• Malfunctioning mass airflow sensor leading to rough idling, engine hesitation, and poor acceleration
• Failing oxygen sensor causing increased emissions and poor fuel efficiency by disrupting the air fuel mixture and fuel injection

ometimes the issue is the sensor itself. Other times, it’s wiring or connection-related. Visual inspection often reveals loose connections or sensor contamination.

The Symptoms of a Faulty Sensor

Sensor problems don’t always mean the car breaks down—but they can affect performance.

Common signs include:

• Poor acceleration and engine misfires affecting the ignition system and spark plugs
• Warning lights for ABS or traction control
• Rough idling or engine hesitation affecting the ignition process and spark plugs
• Poor fuel economy and increased fuel consumption due to more fuel being injected than needed, disrupting the air fuel mixture and causing poor fuel efficiency
• Check engine light or engine light coming on, often with stored trouble codes visible via an OBD II scanner

We often see customers worried about major engine issues—when it turns out to be a relatively small malfunctioning sensor or wiring problem.

Why Sensors Matter for NCT

Faulty car sensors can directly impact your NCT results.

For example:

• Engine faults can affect performance readings by disrupting the combustion process, air fuel ratio, and fuel injection
• ABS sensor issues can trigger warning lights
• Emissions-related sensors like the oxygen sensor or coolant temperature sensor can cause a failed test by affecting exhaust gases and air fuel mixture

That’s why it’s important not to ignore warning lights—even if the car still feels fine.

New vs Used Cars: What to Expect

Sensor issues aren’t limited to older cars.

Newer vehicles have more sensors, which means more potential for minor faults.

Used cars, on the other hand, may experience:

• Excessive oil consumption contaminating sensors, leading to sensor failure
• Previous repairs affecting electronics
• Wear and tear on sensors and wiring connections

At Gerry Caffrey Motors, every car is checked carefully to ensure sensors play their role correctly before sale.

Why Suzuki Models Hold Up Well

Suzuki has a strong reputation for keeping things simple and reliable.

While modern Suzuki models still use advanced sensors, they’re designed with everyday usability in mind.

In real-world Irish driving conditions, we find that:

• Running costs stay reasonable without frequent costly repairs such as catalytic converter replacement
• Faults are easier to diagnose and fix, often by replacing sensors or cleaning components like the MAF sensor and manifold absolute pressure sensors
• Systems are generally robust

That balance is important—especially for drivers who want reliability without unnecessary complexity.

What We See Every Day in Terenure

At our dealership in Terenure, we regularly deal with sensor-related queries.

Customers often come in saying:

• “It only happens in wet weather.”
• “There’s a warning light, but the car feels fine.”

In many cases, it’s a minor failing sensor or wiring connection issue—not a major mechanical fault.

But catching it early through visual inspection and diagnostics using an OBD II scanner makes all the difference.

How to Prevent Sensor Issues

You can’t avoid sensors—but you can reduce the chances of problems.

A few simple tips:

• When cleaning sensors, avoid using high-pressure water jets, which can damage sensitive components
• Maintain a clean engine compartment to prevent dirt or debris from contaminating and corroding sensor heads and wiring
• Inspect wiring connections regularly for corrosion or looseness
• Maintain a clean air intake and replace clogged air filters to protect sensors like the mass airflow sensor and manifold absolute pressure sensor
• Get diagnostics checked early using tools like an OBD II scanner
• Avoid repeated short journeys where possible to allow the engine and sensors to reach optimal operation
• Don’t ignore warning lights or sensor malfunctions
• Keep up with regular servicing, including checking spark plugs and ignition timing

It’s about staying ahead of small issues before they turn into bigger ones.

The Future: More Tech, More Sensors

Cars are only going one way—more technology, more connectivity, more sensors.

That means:

• But also more reliance on electronics and potential sensor failures
• More safety features
• Better engine efficiency and optimal combustion process

Understanding how these systems work (and fail) helps you make smarter decisions as a driver.

Thinking About Upgrading?

If you’re considering upgrading to a newer car, it’s worth choosing a model that balances technology with real-world reliability.

At Gerry Caffrey Motors, we stock carefully selected vehicles—including dependable Suzuki models—with full support on finance and trade-ins.

We also offer flexible finance options and welcome trade-ins, making it easier to upgrade without stress.

Thinking about upgrading to a Suzuki? Visit Gerry Caffrey Motors in Terenure, Dublin 6W—or drop in for a chat and we’ll help you find the right fit.