KNOWN FAULTS · Ford

Ford Fiesta (VII) 1.0 EcoBoost mHEV common problems.

2017–2023 · Hybrid

Sources are not verified in real time and no entry confirms that your car is affected.

2 known faults with sources

Applies if: Weak points of this model from inspections, breakdown statistics and recalls; anything specific to one engine is stated in the sheet.

1.0 EcoBoost oil-pump belt, thermostat and campaigns on the Fiesta (from 2017)Known weak points

Engine / equipment: Ford Fiesta (2017–2023: petrol, mHEV, ST and diesel)
Period mentioned: 2017–2023
Symptoms: Coolant loss from the thermostat housing (often damaging the head gasket); engine failure from the oil-pump belt on 1.0 EcoBoost built up to early 2018; rust where paint chips at the hinges; creaking steering and interior rattles.
Possible cause described: About 1,300 cars in Germany had a quality problem with the oil-pump belt; Ford considers goodwill case by case. Recalls: brake servo (5–20/12/2017), steering column, seat-belt retractor (spring 2021), rear-seat anchors and the traction-battery earth on hybrids (fire risk).
Check for the garage: Watch the coolant; on the 1.0 EcoBoost, use exactly the oil Ford specifies; check every campaign by VIN.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Applies if: Same three-cylinder 1.0 EcoBoost with an oil-bathed belt, here with a 48 V mild-hybrid system.

1.0 EcoBoost wet belt: blocked oil pumpEngine

Engine / equipment: 1.0 EcoBoost three-cylinder with oil-immersed belts
Period mentioned: Approx. 2014–2021
Symptoms: Low oil-pressure warning just before a loss of power; sometimes the engine seizes without warning. With no oil pressure the vacuum pump that assists braking can also stop working.
Possible cause described: The oil-immersed belt material can degrade and shed debris that blocks the oil-pump pickup screen; the tensioner arm can also break. The US agency (NHTSA) is investigating almost 136,000 cars; most failures happened before the belt-change interval.
Check for the garage: With the oil-pressure warning, stop and do not restart. At the garage, check the belt and tensioner and look for debris in the sump and pump screen; use the exact oil Ford specifies and do not stretch the change intervals.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.