Original catalyst (catalytic converter) for Citroën and Peugeot with petrol engines 1.4 VTI and 1.6 VTI. Removed from a car with a raid about 98 000 km. Parts with OEM dog marking guarantee accurate installation and trouble -free assembly into the serial exhaust system, including the correct placement of flanges and threads for Lambda probe.

The catalyst reduces the emissions of unburned hydrocarbons, CO and NOx converted into exhaust gases. A properly functioning unit helps maintain stable emissions and prevents error codes of the control unit (typically P0420 – catalyst efficiency under the threshold). This part is suitable for replacement for worn or mechanically damaged catalyst, or in case of problems with clogging or decay of honeycomb.

Typical symptoms of a defective catalyst are the loss of power, metal rattle from the exhaust, a significant smell of flue gases, the light indicator and the recording of errors related to the catalyst efficiency. Replacing for the original part ensures proper function with ECU factory calibration in VTI engines (EP3/EP6).

Mounting recommendations: Before replacement, let the joints be planted with a release, remove and play the lambda probe into the catalyst threads, always use new seals and fasteners. After assembly, delete the adaptation values ​​and error codes in the control unit, perform a test drive and check of leaks. The approach is usually from the bottom of the vehicle; Recommended use of a workshop jack.

Compatibility: Designed for selected Citroën/Peugeot with 1.4 VTI (EP3) and 1.6 VTI (EP6) engines, eg Citroën C4 II and Peugeot 308.

technical information

• Manufacturer: PSA (Citroën / Peugeot) – original part
• Model: Citroën / Peugeot – engines 1.4 VTI (EP3) and 1.6 VTI (EP6), eg C4 II, 308
• Product codes: 0341n1 (also 0341.n1)
• Other numbers: K418

The condition corresponds to the part used from the car with a raid of about 98 000 km. The ideal choice for fast and economic repair, where you want to maintain original quality and accurate settling without the need to modify the exhaust system.

This used catalytic converter is a direct-fit option for a range of Citroën and Peugeot petrol models equipped with the 1.4 VTi and 1.6 VTi engines. It is ideal for professional workshops and experienced DIY mechanics who need a reliable replacement part with original fitment characteristics. The unit preserves the exhaust routing and mounting points of the OEM component, helping to restore correct emissions control and engine performance where the original converter has become restricted or damaged.

Function And Benefits

The catalytic converter converts harmful exhaust gases (CO, HC and NOx) into less harmful compounds using its ceramic/metallic substrate coated with precious metal catalysts. A healthy converter reduces emissions, contributes to stable lambda sensor readings and supports the proper operation of the engine management system. Replacing a faulty or clogged converter can clear related fault codes and help the vehicle pass emissions testing when the underlying engine faults have been resolved.

Fitment And Compatible Models

Designed for petrol 1.4 VTi and 1.6 VTi engines. Typical compatible models include Citroën C3 Picasso, Citroën C4 II and Peugeot 308. Compatibility depends on model year and exhaust layout—this unit corresponds to the part codes listed below.

How Replacement Is Performed

• Raise the vehicle safely and support on stands to access the exhaust underbody area.
• Remove any heat shields and disconnect upstream and downstream oxygen sensors (label and protect sensors to avoid damage).
• Unbolt flanges or release exhaust clamps and remove the old converter; cutting or grinding may be required on rusted connections.
• Fit the replacement converter using new gaskets/clamps where applicable. Ensure correct orientation and secure all mounting points and hangers.
• Reinstall oxygen sensors, check for exhaust leaks and torque bolts to manufacturer specifications.
• Clear fault codes and run the engine to verify lambda sensor readings and proper operation.

Installation Recommendations

• Use new gaskets and high-quality clamps or bolts when reinstalling the exhaust to ensure a tight, leak-free seal.
• Inspect and, if necessary, replace oxygen sensors when the converter is faulty or sensors show degraded performance.
• Clean mating surfaces and check exhaust hangers and brackets for wear; replace any corroded fasteners.
• Perform a full engine diagnosis to correct causes of rich running, misfires or excessive oil consumption before installing the converter—otherwise premature failure may recur.
• Where cutting of the old exhaust is necessary, ensure proper preparation and use heat shields to protect nearby components during welding.

Most Common Reasons For Failure

• Carbon clogging from prolonged rich running or repeated misfires, which restricts flow and increases backpressure.
• Thermal damage from overheating caused by unburnt fuel igniting on the catalyst (e.g., persistent misfire or fuel system faults).
• Physical damage from road impacts, corrosion or collapse of internal substrate.
• Contamination/poisoning by engine oil, coolant or certain fuel additives that coat the catalyst surface and reduce efficiency.

Technical Information

• Manufacturer: Stellantis (Citroën / Peugeot)
• Model: 1.4 VTi, 1.6 VTi — Typical fitment: Citroën C3 Picasso, Citroën C4 II, Peugeot 308
• Product Codes: 0341P9
• Other Numbers: K485

Notes For The Workshop

As a used original part, the converter shows normal wear consistent with its recorded mileage. Ensure the engine and fuel/ignition systems are in correct operating condition prior to installation to avoid repeat failures. When exchanging components in the exhaust system, always follow workshop safety standards and vehicle manufacturer guidance.

This heat shield is a direct-fit component designed to protect underbody parts and exhaust-adjacent components from excessive heat generated by the catalytic converter and exhaust system. It is commonly searched by OEM numbers 758430880, 758430880-03 and code 1723GS, making it quick to find for professional workshops and DIY enthusiasts. Built for Citroën and Peugeot models with 1.4 VTi and 1.6 VTi engines, the shield helps prevent heat-related damage to wiring, fuel lines, and bodywork while reducing heat transfer into the passenger compartment.

Technical Information

• Manufacturer: Stellantis
• Model: Citroën C3 Picasso; Citroën C4 II; Peugeot 308 (suitable for vehicles with 1.4 VTi and 1.6 VTi engines)
• Product Codes: 758430880, 758430880-03, 1723GS
• Other Numbers: V 758430880-03

Function

The primary function of the heat shield is to reflect and dissipate heat away from sensitive components near the exhaust system, including catalytic converter housings, oxygen sensors, wiring looms and the vehicle floor. Properly fitted, it reduces thermal stress on nearby parts and contributes to safe operation and longevity of underbody components.

Compatibility And Applications

Designed for use on Citroën and Peugeot vehicles equipped with 1.4 VTi and 1.6 VTi petrol engines. Common applications include Citroën C3 Picasso, Citroën C4 II and Peugeot 308. The part is often referenced by OEM/product codes 758430880, 758430880-03 and 1723GS in parts catalogs and service documentation.

Installation Recommendations

1. Allow the exhaust system to cool completely before starting work to avoid burns.
2. Raise and safely support the vehicle on appropriate stands to gain access to the underbody.
3. Inspect fasteners and mounting brackets; apply penetrating oil to seized bolts and let it soak if necessary.
4. Remove old shield carefully to avoid damaging nearby sensors or wiring harnesses. Support the exhaust where required to prevent movement.
5. Fit the new heat shield into position, using original mounting points and hardware. Replace damaged or corroded clips, bolts or grommets with new ones.
6. Tighten fasteners to the manufacturer’s recommended torque values where available. If torque specs are not at hand, tighten evenly to secure the shield without deforming it.
7. After installation, check for interference with exhaust flex pipes, sensors and wiring. Start the engine and inspect for abnormal vibration or contact noises.

Why This Part Fails Most Often

• Corrosion: Prolonged exposure to road salt, moisture and heat leads to rust and perforation of the shield or its mounting points.
• Mechanical Damage: Impact from road debris or contact with uneven terrain can bend or break the shield.
• Vibration And Fatigue: Repeated thermal cycling and vibration cause mounting tabs, bolts or clips to crack or shear off.
• Heat Degradation: Continuous high exhaust temperatures can weaken materials and accelerate failure, especially if catalytic converter temperatures are abnormally high.

Practical Notes For Mechanics And DIYers

When replacing the heat shield, always check adjacent components such as exhaust hangers, sensor cables and heat-insulating sleeves. Replacing worn fasteners and clips during installation prevents rattle and premature re-failure. Keep OEM product codes (758430880, 758430880-03, 1723GS) handy to ensure you order the correct part for the specific vehicle and engine version.

Typical Lifespan

Lifespan varies with driving conditions and climate. In regions with heavy road salt or frequent short trips the shield may corrode and fail earlier. In normal conditions a heat shield should last many years, but visual inspection during routine service intervals is recommended.

Protect your exhaust system and underbody components with this OEM-fit heat shield designed for Citroën and Peugeot 1.4 VTi and 1.6 VTi powertrains. Supplied to fit original mounting points and manufactured to match the dimensions of the factory component, this shield reduces heat transfer from the exhaust and catalytic converter to nearby wiring, plastic parts and the vehicle floor, preventing premature damage and rattling noise. Popularly searched by part numbers 758430780 and 1723GT, this replacement shield is suitable for mechanics and DIY installers looking for a reliable exhaust protection part.

Technical Information

• Manufacturer: Stellantis (Citroën / Peugeot)
• Model: 1.4 VTi, 1.6 VTi
• Product Codes: 758430780, 758430780-03, 1723GT
• Additional Numbers: 1723GT

Compatibility

Common fitment includes (non-exhaustive): Citroën C3 Picasso, Citroën C4 II, Peugeot 308 (including T9). Check the part numbers above to confirm exact fitment for specific variants and model years.

Function And Common Failure Causes

The heat shield protects vehicle bodywork, wiring looms, fuel lines and interior components from high temperatures generated by the exhaust and catalytic converter. It also helps to reduce cabin heat and prevent warping or melting of heat-sensitive parts. Heat shields commonly fail due to corrosion of the metal plate or its fixings, mechanical damage from road debris, or fatigue and loosening of mounting bolts leading to rattling and loss of effective heat protection.

Installation Recommendations

• Safety first: Raise and support the vehicle securely on jack stands or a lift before working underneath.
• Access: Remove any panels or undertrays that obstruct access to the heat shield and locate the mounting bolts or clips.
• Support the exhaust: Where required, support the exhaust or catalytic converter to avoid strain on mounts when loosening fasteners.
• Fastener care: Cut away rusted fixings if necessary and replace studs, bolts or clips with new hardware. Apply suitable high-temperature anti-seize to threads where appropriate.
• Seating: Ensure the new shield sits flush against its supports and that any insulating pads are correctly positioned.
• Tightening: Tighten fasteners to the manufacturer’s torque specification where available; otherwise secure firmly without over-torquing to avoid shearing corroded studs.
• Final check: Start the engine and check for any new exhaust noise or contact; road-test to ensure no rattles develop.

Why Replace

Replacing a degraded heat shield restores protection to nearby components, eliminates annoying rattles caused by loose shields, and reduces the risk of heat-related damage to fuel and electrical systems. Using the correct part number ensures proper fit and long-term performance.

Part Numbers And Notes

This item is commonly searched under part numbers 758430780 and 1723GT. Verify fitment by matching these codes to the vehicle’s existing part for the most reliable replacement choice.