Fiat 500 1.2 69bhp — Exhaust Back Box Corrosion
The mild steel exhaust back box rots through exceptionally quickly, often causing the exhaust to snap and drag on the floor.
Severity
MinorDIY Difficulty
Easy
Est. Cost
£100–£150
OBD Codes
None
Rust
Typical layout and location for the Rust assembly.
Symptoms
- Car sounds much louder/sportier
- Clanking noise from the rear over bumps
- Visual inspection shows the outer skin of the silencer peeling off like an onion
Root Cause
Condensation builds up inside the back box on short city journeys. The mild steel rusts from the inside out. Very common MOT failure.
How To Fix
- Replace the exhaust back box and centre pipe.
- Genuine Fiat exhausts are expensive; aftermarket options (e.g., Klarius or Bosal) are cheap but only last 3-4 years.
- Cost fitted: £100-150.
Estimated Repair Costs
| Repair Option | Est. Cost (GBP) |
|---|---|
| DIY (parts only) | £40–£60 |
| Independent Garage | £100–£150 |
| Main Dealership | £160–£240 |
Other Faults on This Variant
Body Control Module (BCM) / Wiring Loom Failure (Hatch Wiring)
ModerateElectrical gremlins are common on the Fiat 500. The most notorious is the wiring loom snapping where it passes from the body into the boot lid/hatch.
Air Conditioning Condenser Leak (Stone Damage)
MinorThe air conditioning condenser is mounted at the very front of the cooling pack, making it highly susceptible to stone damage from the road, leading to refrigerant loss.
Front Anti-Roll Bar Drop Link Wear
MinorThe front anti-roll bar drop links wear out on heavily potholed UK roads, causing an annoying knocking sound at low speeds.
Disclaimer: Repair cost estimates are indicative and based on community data. Always get a quote from a qualified mechanic before proceeding with any repair.