2018-2024 · 1.0 EcoBoost (100-155 hp) 3-cylinder turbocharged petrol
Popular European compact with efficient but finicky engine. The 1.0 EcoBoost is a clever three-cylinder that's praised for performance but has critical weak points. Early 2018 models may have the troublesome wet timing belt, while mid-2018 onwards switched to a timing chain (check turbo position: rear = chain, front = wet belt). Main concerns: coolant system failures leading to head gasket issues, timing belt degradation on early cars, clutch problems on 6-speed manual and dual-mass flywheel wear, petrol particulate filter warnings, turbo actuator sticking from gentle driving, and battery drain issues. This engine does not tolerate neglect or overheating.
Coolant leak leading to head gasket failure€1,800 - €3,500
Weak coolant hoses, thermostat housing, and cylinder head warp easily from overheating · more· less
The 1.0 EcoBoost has several coolant system weak points. Early models (2012-2014) had problematic degas hoses that would split and dump coolant. Ford issued a voluntary field service action (FSA 4S615) to replace these hoses free of charge on cars built between October 2011 and October 2013. The engine runs extremely hot and does not tolerate even brief overheating. The aluminum cylinder head warps easily, and once warped, the head gasket won't seal properly. Symptoms include white smoke from exhaust on startup, rough running, milky oil, and temperature gauge fluctuations. Head gasket replacement costs €1,800-2,500, but if the head is badly warped or cracked, you need a replacement head (add €500-800) or potentially a complete engine (€2,000-3,500). Monitor coolant level weekly and stop immediately if temperature rises.
Wet timing belt degradation (pre-mid-2018 models)€800 - €3,500
Belt runs in oil and can disintegrate, causing catastrophic engine failure · more· less
Early 1.0 EcoBoost engines (2012 to mid-2018) use a "wet timing belt" that runs inside the engine in oil. This belt can degrade prematurely if oil quality isn't maintained perfectly or if the oil level drops. Ford recommends replacement every 10 years or 150,000 km, but many fail earlier. Preventative belt replacement costs €800-1,200. If the belt fails while driving, it causes timing to slip, resulting in piston-valve contact and complete engine destruction. One owner reported a 2017 Focus 1.0 EcoBoost belt failing at just 55,000 miles, requiring a €3,500 engine replacement. From mid-2018 onwards, Ford switched to a timing chain for the camshafts (though a smaller wet belt still drives the oil pump). To identify which version: if the turbo is at the rear/firewall, it's the chain version; turbo at front means wet belt. All 1.0 EcoBoost mHEV (mild hybrid) models use the chain version.
Clutch and dual-mass flywheel failure (manual)€1,000 - €1,600
125 hp version with 6-speed uses dual-mass flywheel prone to premature wear · more· less
The 125 hp version with the 6-speed manual gearbox uses a dual-mass flywheel (DMF), while the 100 hp version with 5-speed has a single-mass flywheel. The DMF version experiences mass clutch failures, with some owners reporting clutch replacement needed under 20,000 miles despite never having replaced a clutch in 35 years of driving. Ford has not recognized this as a warranty issue. Symptoms include clutch judder when warm, ticking noise when pressing the clutch halfway, and difficulty engaging 1st, 2nd, and reverse gears. DMF costs €400-500 for parts alone, clutch is €75-100, and total job runs €1,000 at independents or up to €1,600 at Ford dealers. Additionally, failing clutch slave cylinders and master cylinder piping can cause similar symptoms. The 100 hp 5-speed manual is more reliable than the 125 hp 6-speed.
Petrol particulate filter (GPF) clogging€200 - €1,500
Warning appears frequently on short journeys: "Exhaust filter limit reached - drive to clean now" · more· less
Many Focus Mk4 1.0 EcoBoost owners report receiving the GPF warning every few hundred miles, particularly those driving mainly short distances. One owner saw the warning at only 300 miles on a brand new car. Another had it appear 3 times by 7,000 km. The GPF has very small capacity (1g vs 8g for a diesel DPF) and fills quickly with soot from short trips or cold starts. The issue only seems to affect the revised chain-driven 1.0 EcoBoost in the Mk4, and Ford hasn't clarified if it's a sensor/software issue or actual filter problem. Some owners observe it happens when outside temperature is below zero and when pushing the throttle too much on a cold engine. The filter should regenerate automatically during highway driving, but if it fills completely, professional cleaning costs €200-400 or replacement costs €1,000-1,500. This is primarily an inconvenience for city drivers, but ignoring warnings can lead to expensive repairs.
Turbo actuator sticking (limp mode)€500 - €2,500
Actuator sticks from gentle driving, triggers EPC light and power loss · more· less
The turbo actuator tends to stick if the car is driven too gently or only for short trips, as carbon builds up. Symptoms include the EPC (Electronic Power Control) warning light and the car entering limp mode with severely reduced power. Ford will not sell the actuator separately from the turbocharger. Actuator-only repair at a specialist costs around €500-600, but if turbo internals are damaged from the stuck actuator, full turbo replacement runs €1,200-2,500. Prevention: use premium fuel and regularly drive the car spiritedly (occasional highway runs with higher RPM) to prevent carbon buildup. Turbos fail more often than they should on these engines, so proper maintenance is critical.
Water pump and thermostat housing failure€600 - €1,400
Electric water pump integrated with thermostat, typically fails 70,000-100,000 km · more· less
The 1.0 EcoBoost uses an electric water pump integrated with the thermostat housing. Failures are common between 70,000-100,000 km. Symptoms include coolant warning light, engine overheating, poor cabin heating, or coolant leaks. The integrated part costs €400-500 due to the electric design. However, labor is extensive (approximately 6 hours) because accessing the water pump requires removing the timing cover and related components. Total cost is typically €600-800 at independent shops or €1,200-1,400 at Ford dealers. Some shops quote additional diagnostic time (around 3 hours) to properly diagnose cooling system issues. This is a critical repair that should not be delayed, as overheating can quickly lead to head gasket failure.
Carbon buildup on intake valves€300 - €600
Direct injection causes carbon deposits, requires walnut blasting around 60,000-80,000 km · more· less
The 1.0 EcoBoost uses only direct injection (not port + direct), making it prone to carbon deposits on intake valves. The PCV system dumps oil vapors into the intake, which bake into carbon. Symptoms include rough idle, misfires, reduced power, and poor fuel economy. Ford doesn't officially recommend a cleaning method and states products like Seafoam could damage the turbo and void warranty. The most effective solution is walnut shell blasting, which requires removing the intake manifold but thoroughly cleans the valves. Professional walnut blasting typically costs €300-600 depending on the shop. Chemical cleaners and manual scraping are largely ineffective. Recommended around 60,000-80,000 km. Installing an aftermarket oil catch can helps trap vapors but buildup will still occur eventually. Regular spirited driving helps minimize but won't prevent the issue.
Battery drain / electrical issues€150 - €650
Battery drains within 24-36 hours, alternator or module issues · more· less
2018-2019 Focus owners have reported battery drain issues where the battery dies within 24-36 hours of parking. Some have had batteries replaced multiple times without solving the underlying problem. Potential causes include: alternator field coil drawing power when car is off (testing shows 5.7 amps through negative cable, dropping to 0.24 amps when alternator unplugged), faulty modules not entering sleep mode properly (removing fuse F38 has helped some owners), and keyless start system constantly pinging the key. Parasitic drain should be under 50mA when everything is asleep; draws over 200mA indicate problems. Alternator replacement costs €540-670. Module diagnosis and repair can cost €150-400 depending on which module is faulty. Some owners need to use battery tenders regularly to prevent drain.
Strong slip and jumping between gears, especially 2nd-3rd and 3rd-4th · more· less
The Mk4 Focus uses an 8-speed conventional torque converter automatic (8F35), which is far more reliable than the notorious PowerShift DCT used in earlier models. However, some owners report uncomfortable jerking during upshifts, particularly from 2nd to 3rd and 3rd to 4th gear at low speeds. The car can "jump 1m forward" during these shifts. Common causes include outdated TCM (transmission control module) software, transmission fluid that needs changing (despite being labeled "lifetime"), and misaligned adaptive cruise control after maintenance. Solutions: TCM software update at dealer (€150-250), transmission fluid change with correct specification for heavy use (€200-350), and learning/adaptive procedures. Check engine and gearbox mounts as well. With proper maintenance and software updates, the 8-speed is generally reliable. Unlike the DCT, this transmission doesn't have widespread catastrophic failure issues.
Manual gearbox issues (6-speed)€800 - €3,000
Clunking when warm, rattling at idle, complete gearbox failure in rare cases · more· less
The 6-speed manual gearbox in the Mk4 Focus has several reported issues. Common problems include: clunking noise when changing gears after 30 minutes of driving (operates smoothly when cold), rattling noise from the gearbox area at idle that disappears when clutch is pressed, and sloppy gear stick feel. Ford changed the gear selector from brass to aluminum about 5 years ago, causing issues with first or second gear engagement. Some owners have experienced complete gearbox failure, with one 2021 Focus ST-Line requiring 3 gearbox replacements in 8 months (first failing at 22,000 miles). Refurbished gearbox replacement costs €1,500-2,000. Cable and linkage adjustments may solve some shifting problems for €100-200. Check for debris preventing the shift plate from moving properly. Overall, the manual gearbox is still more reliable than the old PowerShift DCT but has more issues than expected for a modern car.
SYNC 3 infotainment problems€200 - €1,200
Blank screen, freezing, touch not responding, overheating display · more· less
The SYNC 3 system in the Mk4 Focus has several common issues. Problems include: completely blank/black screen, slow response or freezing when using touchscreen, touch not responding after failed software updates, and screen becoming extremely hot to touch after 15 minutes of driving. The most common causes are faulty APIM (Accessory Protocol Interface Module) on the back of the display, faulty FDIM (Front Display Module - the touchscreen itself), or the LVDS cable connecting them. Troubleshooting steps: perform key cycle (turn off, open driver's door, lock door), check fuses (relay in fuse panel below dash on driver's side), try soft reset (hold Seek Up and Audio Power buttons for 5 seconds), and update software via Ford's official website. APIM replacement costs €600-900, FDIM/screen replacement costs €400-600, cable replacement costs €100-200. Labor adds €100-300 depending on which component needs replacing.
Excessive oil consumption€50 - €2,500
Some engines burn oil, blue smoke on startup, PCV valve issues · more· less
Some 1.0 EcoBoost engines experience excessive oil consumption. Not all of them, but enough that it's worth mentioning. A bit of oil consumption is normal (half a liter between 12,500-mile services is acceptable), but if you're adding more than half a liter between services, something's wrong. Causes include: worn piston rings (usually from running low on oil or overheating), failed turbo seals (letting oil into intake or exhaust), worn valve stem seals (letting oil into combustion chamber), and excessive crankcase pressure from failed/clogged PCV valve forcing oil past seals. Symptoms: blue smoke from exhaust especially on startup or acceleration, and burning oil smell after long drives. The PCV valve costs €20-40 to replace (DIY possible), turbo seal repair requires turbo removal (€500-800 labor + potential new turbo €1,200-2,500), and piston ring replacement requires engine teardown (€1,500-2,500). Monitor oil level weekly and address consumption issues promptly to prevent expensive engine damage.
Requires meticulous maintenance but can be reliable
The 1.0 EcoBoost can reach 120,000+ miles with proper care, but it absolutely requires regular servicing, correct oil grade, and immediate attention to any cooling system issues. The engine does not forgive neglect or overheating. Later models (mid-2018 onwards) with timing chains instead of wet belts are more reliable. Main risk areas are coolant system, timing belt (early cars), clutch/gearbox, and filters clogging from short trips. Avoid if you mainly do short urban journeys under 10 km.
Pre-Purchase Inspection Checklist
General checks
Service history
Complete Ford dealer or specialist records essential. Verify oil changes every 12 months or 12,500 km with correct grade oil (5W-20). Missing even one service is a red flag for this engine.
Tires
Check tread depth (minimum 3mm), age via date codes (max 6 years old), and uneven wear patterns. Common size: 205/55R16.
Cold start
MUST start engine completely cold. Listen carefully for any rattling in first 30 seconds (timing chain/belt issue). Check for white smoke from exhaust (coolant leak).
Body condition
Check for rust, accident damage, paint mismatch. Focus Mk4 is relatively rust-resistant but check wheel arches and sills.
Test drive
Minimum 30 minutes including highway speeds to get engine and gearbox fully warmed up. Many issues only appear when hot.
Specific for this vehicle
Check coolant level and condition carefully
Low coolant or brown/milky appearance indicates serious problems. Check expansion tank for cracks. Look for any coolant residue around hoses and thermostat housing. This is THE critical check.
Verify timing belt vs chain version (if 2018 model)
Open hood and locate turbocharger. If turbo is at rear/firewall = chain (good). If turbo is at front = wet timing belt (get replacement history or budget for it immediately). Chain version is far more reliable.
Listen for cold start timing rattle
Start engine completely cold and listen for rattling in first 1-30 seconds. Brief rattle (under 3 seconds) is acceptable. Rattle lasting longer indicates timing chain/tensioner or belt problems requiring immediate attention.
Check for EPC warning light during test drive
Drive the car normally and watch dashboard. If EPC (Electronic Power Control) light appears with sudden power loss, turbo actuator is likely failing. This is expensive.
Test clutch thoroughly (manual models)
Do 5-6 hill starts in quick succession to check for clutch judder. Try engaging 1st, 2nd, and reverse - difficulty indicates DMF or clutch problems. Press clutch pedal halfway and listen for ticking noise.
Check for GPF warning message
Ask seller if "Exhaust filter limit reached - drive to clean now" warning has appeared. If it comes up frequently (every few hundred km), this indicates problematic driving pattern or faulty sensor.
Check oil level and condition
Oil should be clean and at proper level. Low oil or black/thick oil suggests neglect. Check for white/milky residue on oil cap (coolant mixing with oil - head gasket failure).
Test gearbox operation fully (manual or auto)
Manual: listen for clunking when warm, rattling at idle, check gear stick sloppiness. Automatic: feel for jerking between 2nd-3rd-4th gears, slow downshifts, any knocking sounds.
Inspect for battery drain (if you can)
If possible, ask seller how long car sits without starting. Battery draining in 1-2 days indicates electrical issues. Check that auto start-stop function works properly.
Test SYNC 3 infotainment thoroughly
Check that screen turns on, touch responds correctly, screen doesn't overheat, all buttons work. Try a soft reset (hold Seek Up + Audio Power for 5 seconds) to see if system responds.
Verify all Mk4 recalls completed (see Recalls section)
Contact Ford with VIN to confirm: rear door latch (2018), front suspension bolts (Sept-Nov 2018), brake pedal bolt, seat belt bolts (May-Sept 2019), wiring loom chafe, and oil pump recall if affected.
Recalls and Technical Service Bulletins
Oil pump belt tensioner failure (2016-2018 Focus with 1.0 EcoBoost + auto)Critical - verify completed
Rear door latch incorrect assembly (April-Aug 2018)Verify completed
Front suspension bolts insufficient torque (Sept-Nov 2018)Verify completed
Brake pedal hinge bolt (multiple 2018-2019)Verify completed
Seat belt mechanism bolts insufficient torque (May-Sept 2019)Verify completed
Coolant hose failure - FSA 4S615 (Oct 2011-Oct 2013 1.0 EcoBoost)Voluntary - verify if early car
Contact Ford with the VIN to verify all recalls have been completed. The oil pump recall (23S64) is particularly critical for 2016-2018 models with 1.0 EcoBoost and automatic transmission, as belt failure can cause complete engine seizure. Early Mk4s (2018-2019) had numerous quality control issues with bolts and latches.
Warranty Status
Factory warranty (2 years)Expired on all used cars
Extended warranty availabilityAvailable through Ford dealers
Timing belt extended coverage (some VINs)Check with Ford if pre-2018
All used Focus Mk4 models are outside their original 2-year factory warranty. Ford extended warranty coverage for some coolant-related issues and timing belts on certain VINs. Contact Ford with the VIN to check if your specific car qualifies for any extended coverage programs. Extended warranties are available for purchase but read exclusions carefully.
This report is for informational purposes only and does not constitute professional advice. Estimates may be inaccurate. Always have a qualified specialist inspect the vehicle before purchase. We accept no liability for decisions made based on this information.