Peugeot 307 Catalytic Converter

The catalytic converter in a Peugeot 307 is a key component of the exhaust system. It chemically transforms harmful engine gases into less toxic substances through two main chemical reactions: reduction, which uses rhodium or platinum to reduce nitrogen oxides (NOx), and oxidation, which uses platinum and palladium to convert carbon monoxide (CO) and unburned hydrocarbons (HC) into carbon dioxide (CO2) and water (H2O). To be fully effective, the converter operates at high temperatures, which is why it is placed near the engine, heated by exhaust gases.

The catalytic converter’s function is monitored using two lambda sensors (oxygen sensors) located before and after the converter. They measure the exhaust gases to ensure proper converter operation. If there is a fault or if the converter is removed, the second sensor detects it and the vehicle’s engine control unit (ECU) automatically adjusts the fuel-air mix to reduce toxic emissions. In such cases, the engine warning light will illuminate on the dashboard.

Replacing the catalytic converter involves several precise steps to ensure proper fit and function:

• Disconnect the battery and lift the vehicle safely.
• Remove the silencer by unscrewing the clamps and bolts on the exhaust mounts.
• Detach the exhaust line by loosening clamps and rubber supports.
• Slide the exhaust line rearwards to extract it.
• Insert and install the new catalytic converter and exhaust line carefully.
• Secure all clamps with a torque wrench and verify no contact between the exhaust and heat shields.
• Lower the vehicle and reconnect the battery.

Important notes: Only the catalytic converter itself is replaced; the main exhaust pipe remains intact. The new converter is welded into place. After replacement, the vehicle’s ECU must be properly reprogrammed or configured to meet emission standards and avoid fuel consumption errors.

A malfunctioning or removed catalytic converter causes the Peugeot 307 to enter an emergency mode where the ECU enriches the fuel-air mixture to reduce toxic gas emissions. This leads to several issues:

• Increased fuel consumption
• Reduced engine power
• Illumination of the engine warning light

Driving with a faulty converter is not recommended as it affects engine performance, fuel efficiency, and pollution levels.

While technically possible to drive with a catalytic converter fault, it is not advisable. The engine management system switches to a safe emergency mode which causes increased fuel consumption and reduced engine power. Additionally, your vehicle emits higher levels of pollution, and the engine warning light will constantly flash or stay on, indicating a fault that requires attention.

The Peugeot 307 uses catalytic converters designed for specific engine types, fuel injection systems, and emission standards. Identification depends on the vehicle model, engine size, and EURO standard compliance.

• Converters typically made with stainless steel and high-quality monoliths using platinum, palladium, and rhodium.
• Each part has a reference number or supplier code to ensure compatibility.
• Correct catalytic converter types meet stringent quality and environmental standards.

Checking your Peugeot 307’s VIN and engine details is recommended to source the exact catalytic converter model.

Catalytic converters contain valuable precious metals that enable their pollution-reducing function. These metals include:

• Rhodium and platinum for NOx reduction (reduction reaction)
• Platinum and palladium for oxidation of CO and hydrocarbons

The presence of these rare metals makes catalytic converters both essential for environmental standards and valuable for recycling or resale. This is why failed or removed converters trigger fault warnings and need to be replaced with quality units that meet standards.

If the catalytic converter fault warning light appears or flashes on your Peugeot 307 dashboard, consider these checks:

• Scan the vehicle for fault codes related to sensors or the converter
• Inspect the oxygen sensors placed before and after the catalytic converter
• Verify that the converter itself is not damaged, clogged, or detached
• Check the fuel injection system and exhaust for irregularities or leakages
• Consult a qualified garage for diagnostic and repair if necessary

Early diagnosis and replacing the converter with a quality part help maintain engine performance, fuel economy, and low pollution emissions.

Always ensure the replacement meets Peugeot factory reference and emission standards.