Parts for your 2009 Suzuki Splash-Oxygen sensor

2009 Suzuki Splash oxygen sensor – what it does and when to replace it

Technical sources confirm the 2009 Suzuki Splash uses oxygen-sensor technology on its petrol engines. The Suzuki Workshop Manual for the Splash/Opel Agila B platform (Engine Control System, K10B/K12B) shows an upstream air–fuel ratio sensor (front HO2S) before the catalytic converter and a downstream oxygen sensor (rear HO2S) after the cat for OBD monitoring. The Suzuki Electronic Parts Catalogue (EPC) also lists lambda sensors for 2009 Splash petrol variants by VIN. Independent fitment catalogues from NGK/NTK and Bosch list both front and rear sensors for the 1.0 K10B and 1.2 K12B. By contrast, the 1.3 DDiS diesel (Fiat Multijet) used in some markets typically does not employ a lambda sensor on Euro 4 versions, as referenced in Fiat/Delphi service literature, it relies on MAF/MAP, EGR and, where fitted, DPF differential pressure/EGT sensors.

For 2009 petrol Splash owners, the oxygen-sensor (also called the lambda or O2 sensor) is a quiet achiever. Mounted in the exhaust, it measures oxygen content so the engine computer can fine‑tune fuel injection. The upstream sensor (often a wideband A/F type) keeps the air–fuel mix spot‑on for smooth running, decent power and lower fuel bills. The downstream sensor keeps tabs on catalytic converter efficiency, helping the car meet Euro emissions targets and protecting the cat from unburnt fuel.

There’s no strict replacement interval, these sensors are wear items that can drift with age, contamination, or exhaust leaks. Many last well past 150,000 km, but city driving, short trips, oil burning or silicone/coolant contamination can shorten their life. If the check engine light pops up with codes like P0130–P0161, if fuel economy nosedives, or if the Splash runs a bit rough at idle, a tired O2 sensor could be the culprit.

During servicing, a good workshop will:

• Scan live data and fuel trims to see how the sensor responds when hot.
• Inspect the loom and connector boots for heat damage or corrosion.
• Check for exhaust leaks that can fool sensor readings.
• Verify the cat is healthy before condemning a downstream sensor.

When replacement’s needed, quality matters. Choose the correct sensor type (wideband front vs narrowband rear) as per the VIN and engine (K10B or K12B). Most new sensors ship with thread compound, follow torque guidance in the workshop manual and avoid contaminating the tip. A quick road test and a reset of fuel trims seals the deal. Keep the Splash on top of this little part and it’ll repay with tidy fuel economy and a happy cat.

Note for diesel Splash (1.3 DDiS): many Euro 4 versions weren’t built with an oxygen sensor. Don’t confuse DPF pressure or temperature sensors with a lambda—different jobs entirely.

Popular questions

How many oxygen sensors are on a 2009 Suzuki Splash?
Petrol models generally run two: an upstream air–fuel ratio sensor before the catalytic converter and a downstream oxygen sensor after it. This setup lets the ECU control fuelling precisely and also verify the cat is doing its job. Diesel DDiS variants of this era typically don’t have a lambda sensor fitted.

What are common signs the Splash’s oxygen sensor is failing?
Drivers might notice poorer fuel economy, a rougher idle, hesitation off the line, or a check engine light with lambda‑related fault codes. Sometimes it’s subtle—long‑term fuel trims drift rich or lean—so a scan and a look at live data when the car’s fully hot is the smart way to confirm it.

Can the Splash be driven with a faulty oxygen sensor?
It usually will run, but the ECU may revert to richer defaults, costing fuel and risking catalytic converter damage over time. Left too long, a misreading sensor can mask other issues. It’s best to diagnose promptly and replace the sensor if confirmed faulty.