According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2024 Chevrolet Onix has 2 documented known issues, with 1 rated critical. The most serious is Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime) ($300-$2,500 repair). Across all issues with published estimates, repair costs range from $60 to $2,500. DIY maintenance guides at au7o.io.
On the 2020-2024 Chevrolet Onix, the second-generation Onix and Onix Plus 1.0 turbo (CSS Prime three-cylinder, introduced 2019 for MY2020) use a timing belt that runs immersed in engine oil. GM rates the belt for 240,000 km or 15 years, but Brazilian owners, mechanics and the automotive press have documented widespread premature degradation and outright belt failures between roughly 50,000 and 100,000 km — sometimes under 50,000 km. Oil that does not meet the required Dexos specification (0W-20 for naturally aspirated, 5W-30 for turbo), extended oil-change intervals, sludge or contaminated fuel attacks the belt rubber, which dries, sheds teeth and disintegrates; debris can also clog the oil pickup. When the belt snaps on this interference engine, pistons strike valves and the repair can involve a full cylinder head rebuild or engine replacement, easily exceeding R$10,000. The problem became serious enough that GM South America announced a service action to inspect and replace belts on affected Onix, Onix Plus, Tracker and Montana units, while many warranty claims were initially denied over oil-spec documentation.
Common Symptoms
Ticking or rattling noise from the timing cover area
Rubber debris or dark sludge found in the engine oil
Check engine light with cam/crank correlation faults
Engine cranks but will not start after belt failure
Sudden engine stop with loss of power steering assist
How to Fix
Use only Dexos-certified oil of the exact specification (5W-30 Dexos 1 for the turbo) and change it strictly on schedule at shorter real-world intervals. Independent Brazilian mechanics recommend preventive belt replacement around 60,000-70,000 km instead of the 240,000 km book interval. Have the belt inspected for swelling, cracking or tooth loss at every oil change; if debris is found in the oil, replace the belt and clean the oil pickup. Vehicles with documented dealer maintenance can claim the GM verification/replacement campaign or warranty coverage.
On the 2020-2024 Chevrolet Onix, a chronic and widely reported air-conditioning fault affects second-generation Onix and Onix Plus models (2020+), with similar AC complaints also common on the first generation. The system cools normally for the first few minutes after start-up, then begins blowing warm air even though the compressor stays engaged and refrigerant pressure reads normal; cooling temporarily returns after the car is shut off and restarted. Brazilian AC specialists traced the recurring fault to the expansion valve jamming, which drastically reduces suction in the circuit. Because gauge pressures look normal, shops frequently misdiagnose the problem and replace the compressor (around R$2,000) without fixing anything. The original valve design is considered flawed, so replacement with the same OEM part can fail again; some specialists fit an alternative valve for durability. Complaints about the Onix AC blowing hot air and 'vinegar smell' from the vents are among the most common entries for the model on Reclame Aqui and the Opinautos defect database.
Common Symptoms
AC cools at first, then blows warm air after a few minutes
Compressor stays engaged but no cold air comes out
Cooling returns temporarily after turning the car off and on
Sour or vinegar-like smell from the vents
Weak airflow from dash vents in hot weather
How to Fix
Replace the AC expansion valve (part approximately R$300) rather than the compressor — confirm the diagnosis by checking evaporator suction behavior, not just static pressures. Replace the cabin filter and sanitize the evaporator if there is a sour smell. Under factory warranty, Chevrolet dealers replace the valve free of charge; out of warranty, some specialists install a more durable alternative valve to prevent recurrence.
According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2024 Chevrolet Onix has 2 documented issues. The most frequently reported are: Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime), Air Conditioning Stops Cooling — Expansion Valve Jamming. Of these, 1 is rated critical and should be addressed promptly.
Is the Chevrolet Onix reliable?
The 2024 Chevrolet Onix has 2 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 1 issue is rated critical: Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime). Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Chevrolet Onix problems?
Repair costs for known Chevrolet Onix issues range from $60 to $2,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime), typically costs $300-$2,500 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2020-2024 Chevrolet Onix Premature Failure of Oil-Bathed Timing Belt (1.0 Turbo CSS Prime)?
The second-generation Onix and Onix Plus 1.0 turbo (CSS Prime three-cylinder, introduced 2019 for MY2020) use a timing belt that runs immersed in engine oil. GM rates the belt for 240,000 km or 15 years, but Brazilian owners, mechanics and the automotive press have documented wid… Repairs typically run $300-$2,500. Severity: high.
What is the 2020-2024 Chevrolet Onix Air Conditioning Stops Cooling — Expansion Valve Jamming?
A chronic and widely reported air-conditioning fault affects second-generation Onix and Onix Plus models (2020+), with similar AC complaints also common on the first generation. The system cools normally for the first few minutes after start-up, then begins blowing warm air even… Repairs typically run $60-$450. Severity: medium.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.
