Ford Fiesta
Third generation of the 1.0 EcoBoost Fox block in the Fiesta HJ (2017+). Timing chain instead of wet belt — significantly more robust. Milder EcoBoost variants at 74–103 kW.
Lively EcoBoost
The 1.0 EcoBoost with 125 hp is a little gem: lively, characterful, and in the Mk7 body a real entertainer.
Engine Weaknesses 6
The Gen3 engines also use sensitive coolant hoses at the expansion tank. Plastic fittings can become brittle and cause coolant loss that quickly leads to overheating.
Symptoms: Coolant level drops without visible leak, temperature warning on the dashboard.
The 1.0 EcoBoost uses a wet timing belt for the oil pump. Incorrect oil (without Ford WSS-M2C925-B) or overdue change intervals dissolve the belt. A case involving £3,500 damage at 70,000 km has been documented.
Symptoms: Brief flickering of the oil pressure warning light, engine noise under load, cracked or missing belt teeth found on inspection — often total failure without prior warning.
The front cover seal on early 1.0 EcoBoost engines (up to approx. February 2015) was not oil-resistant. Oil attacks the seal, causing gradual coolant loss. TSI 15-1070 addresses the problem.
Symptoms: Coolant level drops without visible external leak, temperature warning, whitish steam from engine bay.
Boost control solenoid or turbo wastegate can cause boost pressure issues. Intercooler leaks also occasionally occur, causing intermittent power loss.
Symptoms: Noticeable power drop, code P0299 in fault memory, engine in limp mode.
Gen3 engines also occasionally show early catalytic converter failure. Code P0420 cannot be hidden at an MOT and requires replacement.
Symptoms: Engine warning light P0420, flagged at MOT emissions test.
The wastegate actuator rod on the small turbocharger vibrates due to a leaking vacuum actuator. Leads to power loss and fault code P0299 (underboost).
Symptoms: Rattling noise from turbo area, noticeable power drop, fault code P0299, engine in limp mode.
Vehicle Weaknesses 7
Recall 21S13 for 1,568 vehicles (Feb–Mar 2021): seatbelt can tear and thus lose its protective function. Check recall status without delay.
The MK8's manual gearbox jumps out of 1st and 3rd gear. Cause: worn shift forks (sliding pieces) and excessive play at the gear lever. Early diagnosis recommended.
Plastic door edge protector strips break or detach from the door skin. Replacement is surprisingly expensive. Common cause: parking damage and thermal expansion.
The electronic immobiliser develops sporadic malfunctions from 80,000–100,000 km. Tyre pressure sensors become unreliable from 50,000–70,000 km and need replacing.
Rear shock absorbers leak and springs break through corrosion — the same pattern as the predecessor. The loaded rear axle is particularly vulnerable with a fully laden vehicle.
Rust and paint flaking develop at the door hinges on MK8 vehicles from around 50,000 km. Left untreated, rust can spread to the door bodywork.
The SYNC 3 infotainment on the MK8 shows Bluetooth audio drop-outs at low speeds and occasionally frozen screen displays. Software updates from Ford are partially available.
Reports & Tests
189 owner complaints filed with NHTSA (2017–2023). Most reported: Powertrain (52), Engine (32), Other (26).