Mazda MAZDA6 overheating problems

Filed Apr 22, 2026 · Engine · NJ

My cylinder head is leaking coolant. There is a well known and well documented issue with these cylinder heads cracking due to poor casting. This has become such a big issue that Mazda has even recalled the cylinder heads, BUT, only if the engine is equipped with Turbo. However, this issue is becoming enormous even for non turbo owners and is a huge safety issue as it can lead to overheating, stalling, and further damage to other components. I feel very strongly that it is time for Mazda to take some responsibility and extend the cylinder head recall to the non turbo engines.

Filed Apr 7, 2026 · Engine · CA

Car had a coolant leak due to cracked cylinder head that was defective from the factory it was fixed but now the car has engine problems again. Don’t want to keep having these issues in the future

Filed Oct 21, 2025 · Electrical, Seats · 113,500 miles · WI

The contact owns a 2016 Mazda Mazda6. The contact stated that after her husband had driven for approximately 2 hours with the seat heater activated, the passenger’s side seat overheated, and the seat started smoking. The driver stated that the seat heating element overheated and burned a hole in the seat, damaging the air bag located near the seat heater sensor. The dealer was contacted, and an appointment was scheduled. The vehicle was not diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 113,500.

Filed Oct 17, 2025 · Engine · OH

Cracked cylinder head causing oil leak and possible coolant leak. This is a known issue with this year and model. Mazda is trying to suggest the issue is only for the turbo engine, but the non-turbo engine is also defective, per countless reports online. I have a video from the service technician from the mazda dealership, but it is too big to upload.

Filed Jun 16, 2025 · Engine · WI

Coolant leaked into my engine system . Now dealership says a new engine is needed

Filed May 9, 2025 · Engine · GA

Bought used with 47k miles. Two weeks later, took it to my mechanic for an inspection, they found a massive oil leak on the back of the motor. Took it back to the dealership and they diagnosed it as a cracked cylinder head, for which there is a known TSB and warranty extension. Unfortunately, the warranty extension only covers a coolant leak from the cracked cylinder head, not an oil leak. Thankfully, the dealership took care of me but had they not, I was looking at a $7k+ repair on a car I had owned for 2 weeks. In the TSB, Mazda acknowledges that there were both design and manufacturing flaws for the affected model years. In acknowledging the issue, they should have issued a recall for affected vehicles, not a simple warranty extension

Filed Jan 8, 2025 · Engine · KY

Coolant leaks at the cylinder head around the exhaust manifold causing my car to over heat. Also when my thermostat is set to the exact temperature for both sides my driver side blows cold and the passenger side blows hot

Filed Jan 4, 2025 · Engine · NJ

Driving in traffic and the engine temperature warning appeared on dash. Dealer has confirmed there is a large coolant leak from the cylinder head. Mazda released a technical service bulletin regarding the issue affecting Mazda6, cx-5 and cx-9, but I will have to pay for a head gasket replacement.

Filed Dec 4, 2024 · Engine · MA

I am writing to submit a safety complaint regarding my 2019 Mazda 6 GTR. Below are the details of the issue: Vehicle Information: Make: Mazda Model: 6 GTR Year: 2019 VIN: [XXX] Problem Description: My vehicle began to overheat while driving. The vehicle has approximately 35,000 miles and has been meticulously maintained at authorized Mazda dealerships. Mazda Liberty is now asking me to pay approximately $10,000 for a new engine, while Mazda warranty declined to provide support, as I am two months past the warranty period. I have discovered that there are numerous complaints similar engine issues with Mazda vehicles, specifically related to coolant leaks and cylinder head cracks. Incident Details: Date of Incident: [XXX] Mileage at Incident: 35,000 miles Symptoms: Overheating, engine seizure Actions Taken: Topped up coolant, visited local garage and authorized dealership I believe this issue poses a significant safety risk, and I am seeking the federal safety agency's assistance in investigating this matter. Thank you for your attention to this serious issue. Sincerely, [XXX] Cell: [XXX] Email: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jul 9, 2024 · Engine · VA

At less than 95,000 miles, the car suddenly started overheating. Coolant level was fine, maybe ever so slightly low (could still see the coolant in tubing and some in reservoir, which was closer to low than full). Replaced ECT sensor, thermostat and water pump which seemed to fix the issue. Drove for 9-10 days with no issues and it started overheating again. I was able to park quickly afterward at work (<10 seconds). Schedule for drop off at dealer (if car didn't show signs of overheating first (would have called tow truck). Checked fluid levels in car (was ~1Qt low) and topped it off. Drove to dealer (~30min ride) with no issues whatsoever. When dealer looked at it, they said cylinder was warped and leaking, requiring new engine. A just paid off car, with less than 100k miles on it, now needs a new engine that will cost more than half of what it's worth.