2017 Mazda CX-9

August 1, 2023, I discovered the coolant reservoir for my CX9 was empty, had to tow the car to the Mazda dealership, after a few days, the dealership informed me that I have a coolant leak at the cylinder head. This issue is related to the TSB #01-013-21-3753a. The Mazda dealership and Mazda USA informed me that I will have to pay $7,800.00 to have the car fixed, which is ridiculous, but the more serious part is that the car did not gave me any warnings, lights, overheating nothing. If it wasn't because I personally check the car fluid and didn't used the car afterwards, I could have hit the road and be left stranded in the heat or have an engine failure and cause an accident while on the highway.

I experienced coolant leaking from the cylinder head. Mazda is quoting me over $7700 for the repairs. There was a TSB released, there had been numerous revised versions re: the same issue, in Feb 2023 finally including my vehicle. Mazda knowingly put me and my family’s safety in jeopardy by not including me sooner, and now have left me with an astronomical repair bill for an issue they’ve known has existed for years. Had they alerted me when the originally discovered the issue, the vehicle would’ve been under warranty and they would’ve had to replace the parts under warranty.

I was driving on the highway and noticed my car engine temp was way too high. pulled off to the side and found out it lost all its coolant. looked under the car and saw the coolant dripping from the engine. If i didnt notice the car was over heating it could of shut down on me causing a safety issue for me or others. I checked online for the issue and found out this has been a problem for years. the mazda dealership i bought the car from 2 months ago should of known seeing how a TSB was sent out by mazda. There were no symptoms or warnings prior to this.

Engine cylinder cracked causing overheating and need for a total engine replacement. Service technician said that crack was due to an in factory assembly error - overtightening of components of the exhaust system. This is an issue that has happened in other Mazda CX-9's and Mazda is aware of the problem. Vehicle overheated while on a very busy highway and throttled my speed - I could have easily been hit while trying to get to a safe place to park.

Driving home the car said 26 miles to E. while in gear going down the road it popped engine system malfunction and the whole car shut off and wouldn't start. Didn't drive the vehicle for 2 days- filled the gas tank and it drove fine for 5 days. Day 6- 4/8/2023, fine driving down the highway 45 minutes. Go down about a mile and it still doesn't seem right, I move lanes and the thermostat light starts flashing at 260, as soon as I make the turn it tells me to pull over and turn the car off-it was at 270. Go to drive across the street to get coolant later- car stalls when I shift into drive. Park it- get coolant takes an entire jug. Idling a little rough, but not bad. Mechanic he can't see any issues, computer is throwing out fuel system codes but no, issues that can be found. Does a tune up on it, pick it up. Smoking when I start the car and something smells burning. Driving home, it stalls again while in gar at a red light. RPM jumping between 500 and 750 while in gear. Park it for a few hours- everything seems fine. Drive 35 minutes- mostly highway. RPM isn't moving when in park vs neutral. While at last red light before home- engine system malfunction comes on. Driving a few miles down the road still on, temperature at 200. Drive about half a mile down the road- at 260 as I'm pulling into my driveway. Towed to Mazda the next day. Got diagnosis that the head lifted and coolant mixed into oil, flooding engine. Need a new engine and turbo- $10,000 to fix it. Never had issues prior and no signs of anything going wrong. Oil change done 2 weeks prior to this all starting.

While driving, my engine suddenly and dramatically lost power while a temperature warning appeared. I barely made it to a safe spot to park. After having it towed to the local Mazda dealer, the problem was cracks in the cylinder head. This is a known defect from Mazda, which has issued a TSB to dealers but has taken no proactive measures to protect owners. Just 5.5 years into ownership and 51,000 miles, I now must pay for a replacement outside of warranty, costing me over $9,000. All for a dangerous defect that Mazda is aware of and refuses to issue a recall for.

My vehicle has several issues related to a water pump failure in which the check engine light did not remain on. The vehicle began to over heat and slow down on the highway/ roads despite having my foot on the gas. My vehicle is now at Heritage Mazda Catonsville and unable to be read by the OBD reader which may be related to a weak wiring harness reported by other owners of the CX9. It also my be why my check engine light is not on despite having an engine issue. Many others have reported a failed water pump which caused cracks in the head which causes the car to over heat and slow down without notice. Despite having thousands of customers with this issue Mazda has yet to issue a recall.