9.1

really awful
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
1,984 miles

About These NHTSA Complaints:

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« Read the previous 20 complaints

problem #25

Aug 072023

CX-9

  • miles
Driving on a major highway, when the engine overheating temperature light appeared on the instrument cluster. Seconds later it appeared and felt as if the engine would seize and come to an abrupt halt in the middle of a major highway. Thankfully I was able to quickly find a place with room to pull over, avoiding a potential collision. The engine coolant abruptly leaked/exited from the vehicle. I believe there is a service bulletin (No.- 01-002/23), but still no signs of a Recall being issued in reference to this safety concern.

- Somerdale, NJ, USA

problem #24

Jul 142023

CX-9

  • miles
Started smelling coolant through AC and noticing that temp would momentarily spike to 240 before going back down to 200. My independent mechanic diagnosed it as a coolant leak in the cylinder head related to Mazda Tech Service Bulletin 01-002/23 (https://www.tsbsearch.com/Mazda/01-002-23). Took it to Mazda dealership, they confirmed a coolant leak and wish to replace the whole engine. Problem is that vehicle 1) has 105K miles and is not under warranty 2) Mazda engines are on back order and may not be available until November. I am going through an appeal process with Mazda right now to try to get some relief from a 9K repair bill. Disappointed that this known issue ( several threads in the Mazda forums ) is not getting the attention from Mazda that it deserves.

- Rockledge, FL, USA

problem #23

Jul 122023

CX-9

  • miles
A coolant leak appeared around 62,000 miles. Car started overheating and come to find that I had no more coolant left in the reservoir. I filled it back up and drove it to the mechanic, after almost a week in the shop and have been quoted over $2k for the fix. There is a TSB out on this issue. It is a known issue apparently from a casting defect in the heads / block.

- Henderson, NV, USA

problem #22

May 142023

CX-9

  • miles
A coolant leak appeared around 60,000 miles. I caught it in the right time as I had no more coolant left in the reservoir. I filled it back up and drove it to the Mazda dealership - I did not overheat at all so no warning lamps appeared. Upon taking it into the Mazda dealership, the engine was pulled and it was discovered that the cylinder head was cracked. This requires a new engine. There is a TSB out on this issue. It is a known issue apparently from a casting defect in the heads / block.

- Bethel Park, PA, USA

problem #21

May 252023

CX-9

  • miles
coolant leaks at the cylinder head around the exhaust manifold, safety was compromised by car overheating in the middle of extremely high level traffic, problem confirmed by Mazda dealership, only inspected by dealership, there was no warning indicators from the vehicle. I could smell antifreeze the day before it overheated.

- Summerville, SC, USA

problem #20

Apr 082023

CX-9

  • miles
A known faulty cylinder head in these cars is breaking. A simple search of the web shows numerous owners have had the same problem. Mazda dealers KNOW it is a problem. They have upgraded the part, but it comes at a cost of approximately $7800 to owners of said vehicles.

- Villa Rica, GA, USA

problem #19

May 082023

CX-9

  • miles
Engine cylinder head cracks open due to bad design where turbo puts too much weight and vibration resukting in coolant leaking out of engine. Mazda has a bulletin out for this issue and I took it to a Mazda dealer for repair. They confirmed this was the issue.

- Buford, GA, USA

problem #18

Apr 272023

CX-9

  • miles
Bought car new in 2018. At 72,600 observed coolant leaking from backside of motor. Carried to Classic Mazda of Texarkana, TX for diagnostic test. Has a cracked cylinder head.Mazda refused to pay to fix or assume any responsibility for the design flaw. Turbo charger is too close to the cylinder head causing heat issues over time resulting in cracked head/coolant leak.

- Omaha, TX, USA

problem #17

Jan 052023

CX-9

  • miles
Coolant leak at cylinder head. It is available for inspection. Driving on the highway and the car overheating light came on. Yes it has been reproduced and diagnosed as part of the TSB 01-013/21. No warnings, no notice of leaks before this happened. Noticed this in January - and thought it was just a one off and had the coolant topped off. Nothing happened until a month later that is when I took it to the mazda dealer. Safety issue as no one knows about it until their light comes on and they take it to the dealer to look at. Having this happen in the middle of nowhere on a highway with three small kids is a nightmare. This issue needs to be investigated. It is definitely a safety issue. It is shocking to know that Mazda has known about this for a couple years now based on the date of the TSB. A letter, at the very least, should have been sent out to all owners. Instead they let us all sit with a ticking time bomb that will be cost prohibitive to fix.

- Hanover, PA, USA

problem #16

Mar 182023

CX-9

  • miles
I own a 2018 Mazda CX -?" 9 with only 53,300 miles. I noticed something was wrong with my engine and had no idea what the issue was. My car would not shut off immediately when I turned it off and the fan was on super high speed. The day before my appointment with my mechanic, the engine light turned on. I was stuck in a parking lot and a friend suggested I use his car to go buy coolant just in case it was needed. Sure enough, I was completely out of coolant. When my mechanic inspected the car he told me I had a coolant leak and suggested I take it to the dealer as they would know immediately what the problem was. I started researching to see if this was a defect and sure enough, Mazda has been aware of the defect with the cylinder head (TSB) not supporting the turbo of the engine causing it to crack and mix with the engine oil in various models for years, yet continue to sell cars with this known defect. I understand that it may not be life threatening yet! But it could have been should my engine had blown while I was on the freeway causing a horrific accident. How are they allowed to continue manufacturing and sell cars with a known issue for years and not even be reuqired to make a recall to have the part replaced with a stronger one? This is issue is happening to 100's of customers worldwide. This is something that should be investigated.

- Granada Hills, CA, USA

problem #15

Feb 082023

CX-9

  • miles
Coolant leak into cylinder head, resulting in overheating and blown head gasket. Repair cost was $7k to resurface cylinder head and replace gasket. Repair did not fix issue, likely due to unseen cracks or warping to cylinder head. Will require rework, likely entire engine replacement, as the defect cannot be corrected.

- Wimberley, TX, USA

problem #14

Feb 112023

CX-9

  • miles
This weekend Mazda CX-9 started leaking coolant from the firewall side.

- Itasca, IL, USA

problem #13

Jan 142023

CX-9

  • miles
Driving the car home from work, the engine temperature gauge started to go up high. I added coolant that same night. Went to the dealership for a check up. I was told the coolant was coming out from the back of the engine and will need to partial repair the engine. Only 75k miles in the engine and that was an estimate cause I could need a brand new engine. Now I-€™m stranded with out a car waiting for a response. MAZDA should do a recall regarding that issue cause I-€™ve seen a lot of CX9s have the same issue. THATS NOT GOOD FOR RELIABILITY.

- Brockton, MA, USA

problem #12

Oct 312022

CX-9

  • miles
After owning this used vehicle for about 11 months, the engine temperature gauge indicated the car was running hot - about 240 degrees. After inspecting the vehicle at home, we added coolant to the system. This helped maintain engine temperature temporarily, but we noted over the next several weeks that the coolant was dropping rapidly. After inspection by a Mazda dealer, it was concluded that the cylinder head needed replacing.

- Clawson, MI, USA

problem #11

Oct 092022

CX-9

  • miles
I have a 2018 Mazda CX-9 with about 66,000 miles. I noticed a coolant leak when my SUV sat in my driveway. It was there each night after driving the SUV. I took the vehicle to a Mazda dealer who stated that the coolant leak is from a cracked cylinder head. A cylinder head should not crack in 4 years and only 66,000 miles. This is a known Mazda issue for this year make and model.

- Lancaster, PA, USA

problem #10

Oct 062022

CX-9

  • miles
I noticed a smell of antifreeze. After taking it back to dealership, I find out it has a cracked head. It has never ran hot.

- Hazlehurst, GA, USA

problem #9

Jul 182022

CX-9

  • miles
The cylinder head failed causing a massive leak of engine coolant. This occurred initially at highway speeds which caused potential danger to myself and others around me as the car was required to pull over immediately. The problem was confirmed by the dealer and is known to the manufacturer as indicated by TSBs. The part was inspected and replaced by a new, redesigned part at the owner's expense.

- Lexington, SC, USA

problem #8

Oct 062022

CX-9

  • miles
the cars engine makes loud rattling noise and slips gear. the vecicle jerks hard and feels as if transmission is slipping. car hesitates when i shift into gear, followed by a jerking and jolting into gear. my brakes are replaced frequently. mazda at 65643 miles on car found excess operating noise coming from engine coolant/water pump due to internal bearing failing. they replaced the water pump. software (pyd8-18881-f) replaced. the vehicle has 74000 miles and has same problem. when stopped at a traffic signal it lunges forward at times. and shifts slow to fast gears. this problem is not resolved. the first time it was allegidely fixed was 22Dec2021 it is now 05Oct 2022

- Murrieta, CA, USA

problem #7

Aug 242022

CX-9

  • miles
I purchased my 2018 Mazda CX-9 Grand Touring CPO with 39k miles and was sold the life time extended powertrain warranty through the dealership. The car now has 74k miles. While sitting idle at the school bus stop in my neighborhood waiting for my daughter the temperature gauge light comes on. I immediately drive home (exactly 0.3 miles) not going over 10mph back home, park call a tow truck company to tow it to the Priority Mazda dealership in Tysons Corner, VA from which I bought it. After a few days the mechanic calls and tells me there is a coolant leak and the repairs for the Cylinder Head should be covered under my lifetime extended warranty. A few days later I get a text message from the service rep that states. "Unfortunately, the extended warranty has denied coverage of the Cylinder Head, stating it to not be an internally lubricated issue....we need to fully inspect to determine what is needed (cylinder head or full engine due to overheating) Cost of teardown $1,432." After speaking to the service rep directly he then tells me the coverage was actually denied because Mazda put out a TSB on this known issue which voided my extended warranty on the cylinder head. This TSB bulletin no.01-007/22 was just issued 2 months before this happened. We should not be responsible for a known engine issue on Mazda's flagship car after purchasing an extended warranty for this very reason.

- Springfield, VA, USA

problem #6

Aug 192022

CX-9

  • miles
While commuting home on 8/19/22 my CX-9 began overheating and coolant temp. warning light illuminated on dash. This was a dangerous situation as I had to stop in the middle of traffic for fear of ruining my car and risk getting rear-ended and also navigate to the shoulder of the road. Took the car to the dealership where they confirmed P111A engine overheated DTC and coolant leak. CX-9 has a cracked cylinder head, the exact problem outlined in Mazda TSB 01-013/21. This happened at 61, xxx miles...roughly 1,000 miles outside the powertrain warranty however it's highly likely this crack and leak developed well before the end of the powertrain warranty period.

- Vancouver, WA, USA

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