✓ The faults of this engine were checked against sources (10/2026). Each item has at least two independent sources or an official recall or parts-maker technical note.
Timing chain stretch or rattle (0.9 TCe H4Bt)
usually 100,000–180,000 km · Medium risk
engine codes: H4B, H4BT
Signs: Rattle for a few seconds on cold start, later camshaft/crankshaft correlation fault codes and engine light
Fix: Do not ignore the noise; measure chain stretch (live data or inspection) and replace chain, tensioner and guides; change oil more often than the long factory interval
€600–1,200
Coolant leak at plastic thermostat / water housing (0.9 TCe)
usually 50,000–150,000 km · Medium risk
engine codes: H4B, H4BT
Signs: Coolant level drops slowly, smell or traces of coolant, temperature warning; if missed the engine overheats
Fix: Check the coolant level regularly; replace the thermostat housing or water outlet with its seals; after any overheating check the head gasket
€150–400
Coolant in ignition coil wells, misfire (1.0 TCe H4Dt, ~2019-2022)
usually 20,000–240,000 km · Medium risk
model years 2019–2022 onlyengine codes: H4D, H4DT
Signs: Misfire, rough running, flashing engine light, coolant level dropping without an outside leak
Fix: Do not just replace the coil: find where coolant enters the coil wells (dealer has a repair procedure on the engine); ask about goodwill on cars still young
€150–1,500
Turbo wastegate rattle or boost leak, power loss (1.0 TCe H4Dt)
usually 10,000–120,000 km · Wear part
model years 2019–2023 onlyengine codes: H4DT
Signs: Metallic rattle from the turbo when lifting off or at low load; sometimes power loss with an underboost code
Fix: Dealer ECU update (Renault technical note) for the rattle; for power loss check the turbo air hose and the boost control valve before replacing the turbo
€0–600