10.0

really awful
Crashes / Fires:
1 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
9,588 miles

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« Read the previous 20 complaints

problem #25

Dec 132022

CX-9 4-cyl

  • miles
My engine head cracked whiling driving. sudden lost of complete power in houston texas at a 75mph speed. Was able to safely pull to the side. took it to the dealer where they confirmed it was a cracked engine head. Its a common issue with this model from 2016-2019 no warning light came on just lost 90% power. was able to restart and drive the 7 mins to the dealer.

- Conroe, TX, USA

problem #24

Dec 092021

CX-9

  • miles
At an intersection the engine stalled and car was extremely hard to restart (took several minutes). I later noticed oil and coolant dripping from the engine and coolant mist/vapor from the exhaust. Later I learned it was possibly related to Mazda's own TSB Bulletin No: 01-013/21 where a manufacturing defect caused coolant to enter the combustion chamber and hydro lock the engine (where I stalled and had hard time restarting). I had to have the car towed home. At home I noticed the passenger underside of the vehicle coated with oily/watery residue of possible oil or oil/coolant mix. Vehicle had 66K miles on and Mazda dealer refused to fix.

- Myrtle Beach, SC, USA

problem #23

Dec 202022

CX-9

  • miles
I am being told by the dealership service center that there is a coolant leak from the engine. A previous coolant look due to a hose was repaired but this is a separate issue related to the TSB for coolant leak at the cylinder head Bulletin 01-007/22

- Indianapolis, IN, USA

problem #22

Nov 152022

CX-9

  • miles
Cracked Cylinder Head due to Coolant Leak - SB 01-013/21. This is a known issue with Mazda, yet it has happened with the vehicle being serviced regularly. This is happens directly after the warranty period and it is not being covered.

- Rosenberg, TX, USA

problem #21

Nov 062022

CX-9

  • miles
A strong coolant smell was noticed in the interior of the car and from the engine compartment. The diagnosis from the Mazda service facility was that there was coolant leaking from the head on the engine. Eventually this would have led to overheating of the vehicle which could have resulted in significant engine damage. The manufacturer has issued a technical service bulletin (TSB) for this problem. Cracking of the head that leads to coolant leaks is a known problem with this engine in several different models of Mazda including CX-5, CX-9, and Mazda 6. Our vehicle has remained in the shop since it was taken in on 11/8/2022.

- Bethesda, MD, USA

problem #20

Aug 222022

CX-9

  • miles
Due to Mazda's known problem in the design of their engine at just over 80,000 miles the head and turbo of my engine have cracked. They have issued a service bulletin to their dealerships, which acknowledges this as a common problem. (Technical Service Bulletins (TSBs) are official communications between Mazda & its dealerships that describe processes for troubleshooting or fixing certain common problems.) Unfortunately, for most Mazda CX-9 owners this bulletin was issued after most have just passed their 60,000-mile warranty, thus allowing them to get away with designing an engine for a fairly expensive car that is only good for 80,000 miles. Mazda further acknowledges this as a problem as newer engines are no longer designed the same way to avoid the problem and any parts put on the engines that are failing are of the new design because the OEM parts will just fail again. Dealing with Mazda customer service is a joke, they are rude, refuse to answer questions and will not call you back with answers when they say they will.

- Elkland , MO, USA

problem #19

Sep 102022

CX-9

  • miles
The cylinder head has cracked and it leaks antifreeze. This can cause the vehicle to overheat and destroy the engine. It is apparently a known issue as Mazda has issued 3 technical service bulletins addressing the problem. They have even redesigned a new part to replace the faulty one. In the TSB they even address that the crack may be caused by "stress generated during production" In other words, its a known problem yet they havent issued a recall on it. Im guessing they havent issued a recall because the quote for the repair was $5000. At $5000 to repair the faulty part it would be quite the expensive recall for the company.

- Blair, NE, USA

problem #18

Aug 232022

CX-9

  • miles
My Engine is over heading because it has a crack and losing coolant externally. There are 74773 mills on my car. Every 3 weeks I have to put a gallon of coolant in the engine. if I don't put coolant, the engine can stop working on the freeway causing bodily injury to me and other drivers.

- Rancho Mission Viejo, CA, USA

problem #17

Jul 302019

CX-9

  • miles
Engine Coolant Leaking from rear of engine near Exhaust / turbocharger at Cylinder Head. No Warning Lights indicating problem until coolant level low causing overheating and fire risk. Rear Brakes not releasing completely from "City Mode" where brakes are kept close to rotor "to increase braking response in City driving" - causes premature brake wear, warped brake rotors (reoccurs within 10K miles from new / replaced rotors) Front Bumper Fascia keeps coming loose at clips near headlights on both Driver and passenger side. Had replaced at dealership 3 times, but continues. Bumper coming loose and can obstruct headlights while moving around at highway speeds

- Queen Creek, AZ, USA

problem #16

Jul 282022

CX-9

  • miles
2016 cx9, after reviewing online. Known issue with coolent and engine cylinder. Water coolent leak to engine head. Dealer asking 75k to replace engine. Mazda refused to acknowledge the known issue.

- Sachse, TX, USA

problem #15

Apr 212022

CX-9

  • miles
On 04/21/22, I took my car to the dealer after noticing antifreeze on our garage floor and a burning smell. NO check engine lights had illuminated. They proceeded to tell me that there was a coolant leak from head/block and cavity leak (something about channel pressure). They also stated this was a casting flaw during manufacturing of the engine. They told me I needed a whole new engine for $8,479.97! Mazda corporate refused to replace the engine at their cost because I had 64,575 miles on it and it was out of powertrain warranty. I called them and asked to speak to a supervisor and never heard from them. I called on 4/26, 4/27, 4/28, 5/4, 5/5 (5 times), 6/9, & 6/20. I finally gave up agreed to pay $7,479.97 (the dealer gave me $1,000 off). I received the car back on 05/20 and it would not start later that day. They towed it back to Mazda and they replaced the crankshaft sensor that was damaged upon install of the new engine. I received it back again on 05/31 and later in the day, the check engine light came on and the automatic braking system engaged while I was driving (thankfully only 40 mph). I managed to pull over in a turn lane before the engine died. I was so thankful I did not make it onto the interstate I was about to enter! Mazda came and picked me up and later got my car. They could not figure out why it was dying and finally got it to recreate it. They replaced another engine sensor and then drove it a lot to make sure it was truly fixed. I finally received my vehicle back on 07/07. I am afraid to take my car out of town and it makes me nervous it will die and automatically start braking again. They KNOW this is a manufacturer issue and they refuse to take responsibility. I am so disappointed in them. This is a huge safety issue. I am also lucky I didn't blow a head gasket before I took it into the shop the first time.

- Knoxville, TN, USA

problem #14

Jun 302022

CX-9

  • miles
Traveling on the highway going on a road trip. Had vehicle inspected prior and no fuel system problems were noted. I was going 75mph with my family when there was a coasting feeling in the car. I looked and my check engine light popped on and my car immediately would not accelerate and we quickly lost speed. By the grace of God were we able to pull over safely! Code P0132 was the engine code and after an hour, the engine light went back off and we were able to keep a safe speed traveling home. After speaking with a mechanic and dealership, I learned that this was a common problem with the Denso fuel system. My vehicle was not included in a recent recall that included a different year of my vehicle. If manufacturers are aware that a major defect is out there, how many people have to have an accident or potentially cause a huge accident because a car made 2 years prior with the same part from the same manufacturer has the same dangerous problem? It-€™s ridiculous and I hope you look at this near fatal issue that has effected thousands of people, whose vehicles-€™ were made in 2017, 2016, 2015 and are not included in the recall.

- Katy, TX, USA

problem #13

Jun 152022

CX-9

  • miles
I droved my 2016 cx-9 off highway and idled it at front of restaurant, suddenly the engine coolant overheat light came on, shut engine off and found leaking coolant on the ground near the rear of engine bay. Brought the car to Corpus Christi Mazda, found out leaks come from cylinder head crack, happens to cx-9 manufactured before June 20, 2020 according to Mazda TSB 01-013/21. I was quoted $3380 to replace the cylinder head out of pocket because the car is just out of powertrain warranty. I contacted Mazda headquarter for covering the cost out of goodwill since this is due to manufacture defects of cylinder head. Mazda refused to pay.

- Corpus Christi, TX, USA

problem #12

Apr 122021

CX-9

  • miles
Cracked cylinder head due to manufacturing defect, left stranded at car wash with no engine coolant due to issue, took several months without a vehicle before it was replaced by Mazda. The vehicle has been repaired. I was left unable to drive in hot weather and could not use air conditioning while waiting for assistance. Dealer had seen the issue before, reported by many on online Mazda forums. There were no warning lamps prior to the incident happening.

- Goshen, KY, USA

problem #11

Feb 142022

CX-9

  • miles
Purchased the car used with 67k miles on it. Within 2 weeks of purchase warning lights went off saying that the engine was overheating due to censor malfunction. After three visits to mechanics (2 to the dealership and 1 to a private mechanic) it was determined that coolant was leaking into the engine causing the engine block to crack. This of course means that the engine will have to be replaced in order for it to be useable. That repair has been quoted by the dealership as a $14,000 repair. For a car that has less than 70k miles.

- Centerville, TN, USA

problem #10

May 132022

CX-9

  • 134,000 miles
15 minutes after getting a wheel bearing replaced at the dealer, my engine coolant high temperature warning came on (never before seen). This occurred while I was on the interstate with no safe place to stop. When I was able to safely stop, I called the dealer. They said bring it back. I was unwilling to drive that far so chose the closest Mazda dealer. They informed me I have a cracked cylinder and the coolant is leaking into exhaust system. I was told the only option due to the mileage on the car (134,000) is to replace the engine for $8,000. This appears to be a known issue so I am shocked that it wasn't being checked for prior to the problem.

- Schoharie, NY, USA

problem #9

May 012022

CX-9

  • miles
Cylinder head cracked, leaking coolant and causing engine overheated, potential fire hazard. Coolant also leaked and mixed in with oil cycling through engine, causing permanent damage to the engine, resulting engine to be fully replaced

- Adelanto, CA, USA

problem #8

Nov 262021

CX-9

  • miles
Dealer diagnosed manufacturing defect that caused crack in head. {Which could lead to engine failure, and subsequent accident due to engine failure during operation.} Engine lost coolant. No overheating noted. No warning/error codes noted.

- Houston , TX, USA

problem #7

Oct 272021

CX-9

  • 120,000 miles
The contact owns a 2016 Mazda CX-9. The contact stated that while driving at an undisclosed speed, the air conditioning became warm and the fan was abnormally loud. Additionally, the engine temperature gauge was high. The contact pulled over and refilled the coolant reservoir. The vehicle was taken to an independent mechanic who initially diagnosed that the water pump was faulty and needed to be replaced. However, when the contact took the vehicle back to the independent mechanic for the water pump replacement, the mechanic diagnosed that the cylinder head was warped and referred her to the dealer. The vehicle was not repaired. The dealer was made aware of the failure and informed the contact that there was no recall associated with the VIN. The manufacturer was made aware of the failure and informed the contact that there was no recall associated with the VIN and referred the contact to file a complaint with the NHTSA. The failure mileage was approximately 120,000.

- Fayetteville, NC, USA

problem #6

Nov 162018

CX-9 4-cyl

  • 17,061 miles
11/16/18 towed for inoperabilty. Stuck fuel injector/ ruined engine. All panel lights came on. Kept car for 57 days. Fuel injector # 1 failed. We were driving onto interstate. While working on car, exhaust stud broke off into turbo charger housing. Drilled out and rethreaded took back to Mazda dealer to C/O about swooshing noise in R dash said they did not hear. This occurring with acceleration 2/7/19 while driving out of state on interstate, swooshing noise R dash lost acceleration while passing. St peters, mo dealership had to put back on the turbo hose & clamp 5/6/19 back home and again heard the swoosh noise on acceleration. Dealership replaced gasket to turbo charger / air leak with smoke test 9/14/19 again became inoperative while driving out of state immediately after passing large truck, lost acceleration with pedal to carpet. Was told in limp mode smelled something in car compartment. Stuck on narrow county road. Limped to turn off. On inspection by tow truck person, stated was pouring gasoline from front of car. 'this could have caught fire due to 90+ degree temp in tex. Fuel injector # 4 exploded mechanic on inspection told serv mgr this car was put back together in a shoddy manner. The hose to fuel injector had previously been routed wrong when engine replaced. Now waiting on malfunction of fuel injector 2&3. scared to drive car. C/O to Mazda customer rep. His response well U have warranty until 4/2024. That is B/C we took extended warranty. Hollingsworth Mazda in baton rouge, la closed reason unknown. Consumer stated error to vehicle speed instead of 10-15 mph.

- Baton Rouge, LA, USA

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