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.

Product Overview

This aftermarket-used catalytic converter is a direct-fit unit originating from a Citroën/Peugeot vehicle equipped with the 1.4 VTi or 1.6 VTi petrol engines. It bears the reference codes K485 and 0341P9 and comes from a donor car with 68,000 km. Ideal for professional workshops and skilled DIY mechanics, this unit restores exhaust flow and helps the vehicle meet emissions control by converting harmful gases from the engine exhaust.

Technical Information

• Manufacturer: Stellantis (Citroën / Peugeot)
• Model: Citroën C3 Picasso; Citroën C4 II; Peugeot 308 (1.4 VTi, 1.6 VTi)
• Product Codes: K485, 0341P9
• Other Numbers: Donor Vehicle Mileage: 68,000 km

Function and Typical Symptoms

The catalytic converter reduces hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) by passing exhaust gases through a precious-metal-coated ceramic or metallic substrate. Typical signs of a failing or blocked catalytic converter include reduced engine power, sluggish acceleration, increased fuel consumption, rattling noises from inside the converter, strong sulfur/rotten-egg smell, and illumination of the Check Engine Light (often P0420 or similar codes). Note that similar symptoms can also be caused by faulty oxygen sensors, exhaust leaks or engine misfires, so a full diagnosis is recommended before replacement.

Why The Part Most Commonly Fails

Failures usually result from secondary damage rather than simple wear: contamination by engine oil or coolant (indicating internal engine issues), repeated engine misfires that overheat and melt the substrate, physical damage from road impacts or corrosion of the housing, and clogging from soot and carbon buildup. In many cases, converter failure is a symptom of an underlying engine problem that should be addressed to avoid premature failure of the new unit.

Installation Recommendations

Recommended for experienced mechanics and competent DIYers. General installation guidance:

• Work on a fully cooled vehicle and support it securely on jack stands or a lift.
• Disconnect the battery before starting work to avoid electrical hazards.
• Remove upstream and downstream oxygen sensors first and inspect them for wear; replace if necessary.
• Support the exhaust system while detaching mounting points, clamps or bolts. Replace gaskets, seals and any corroded hardware to ensure a proper seal.
• Fit the converter in place, tighten fasteners to the manufacturer’s torque specifications and reconnect oxygen sensors. Apply a small amount of anti-seize to sensor threads only if the replacement sensor is not pre-coated.
• After installation, clear any stored codes with an OBD scanner and perform a test drive to confirm correct operation and that no fault codes return.

Practical Notes for Buyers

This unit is suitable for vehicles listed in the Technical Information. Verify engine family and part numbers when placing an order to ensure compatibility. Because converter failures are often caused by engine faults, inspect ignition system, fuel trim, and cooling system if the original unit failed. Replacing damaged sensors and exhaust gaskets at the same time reduces the chance of repeat visits.

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.