general problems of the 2016 Mazda CX9 - part 2

64 problems related to engine and engine cooling have been reported for the 2016 Mazda CX9. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2016 Mazda CX9 based on all problems reported for the 2016 CX9.

36 Engine And Engine Cooling problem

Failure Date: 06/12/2023

My 2016 Mazda cx-9 2. 5l touring has approx 67,500 miles. I noticed the "sweet" smell of coolant after driving. The temp gauge was not showing signs of overheating. I checked under the hood and coolant level in radiator and reserve tank were normal. I also did not see any coolant leak/patches under the car. Few days later the car temperature gauge shot past the 1/2 mark. I stopped the care let it cool and checked under hood. Radiator was empty but reservoir tank was still full. There were signs of coolant drips underneath car on the plastic cover below the area of the water pump (passenger front wheel side). Waiting to have car assessed/fixed by mechanic.

37 Engine And Engine Cooling problem

Failure Date: 05/15/2023

Cylinder head had a crack in it and had to be replaced.

38 Engine And Engine Cooling problem

Failure Date: 04/29/2023

While driving on the freeway in stop and go traffic the engine warning light came on. A few minutes later the data screen stated that I needed to pull over immediately as my engine was overheating. I was on a stretch of the 5 freeway north of oceanside with no exits for several miles. I pulled over and when the light went off I got back on the freeway to try to make it to an exit. I repeated this process until I was able to exit and pulled in at the first mechanic I came to. The vehicle was losing power at that point. Pulling in and out of the traffic was hazardous to both me and the other drivers. When they inspected my car, they determined that the coolant had been leaking for a significant period of time as demonstrated by the worn spot on the pipe it had landed on. Further inspection revealed a blown head gasket. When a new head gasket was ordered from the local Mazda dealership, the mechanic was surprised to learn that Mazda had four of these parts in stock as most dealerships would have to order the part. The Mazda service department told him that they had four head gaskets in stock because this happens pretty often. My research on this site and on the Mazda forum indicates that this is a known defect to Mazda. This vehicle has just over 56,000 miles on it. It is regularly serviced. There was no warning light prior to this incident, in fact, the blue light indicating the engine was cool had regularly appeared whenever I started the vehicle. I have the replaced head gasket in my possession, should inspection of the part be necessary. I have reported this issue to Mazda but have been advised it is unlikely they will reimburse me.

39 Engine And Engine Cooling problem

Failure Date: 01/05/2023

Head gasket blew in a 2016 Mazda Cx9 while driving causing us to as safely as possible quickly get off the road from the middle lane of an interstate. This is from a known coolant leak in the cylinder head from service bulletin 01-013/21.

40 Engine And Engine Cooling problem

Failure Date: 12/20/2022

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.

41 Engine And Engine Cooling problem

Failure Date: 12/13/2022

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.

42 Engine And Engine Cooling problem

Failure Date: 11/15/2022

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.

43 Engine And Engine Cooling problem

Failure Date: 11/06/2022

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.

44 Engine And Engine Cooling problem

Failure Date: 09/30/2022

2016 Mazda cx-9 2. 5l turbo touring with 93,197 miles. In September of 2022, I noticed a sweet smell coming from the engine bay after coming home from work. I took my car to my mechanic on 9/30/2022 for an oil change and asked if they could figure out the "sweet smell" coming from the engine bay. When they were doing the oil change, they checked for leaks and noticed that coolant was leaking from cylinder head. Since it was out of warranty, I had my mechanic repair the issue. Which resulted in a complete cylinder head replacement. This is a know issue by Mazda and there is lots of documentation online for this as well. There has since been updated parts to repair this issue, but this should be a recall covered by Mazda. Cause this repair cost me $5,700 out of pocket.

45 Engine And Engine Cooling problem

Failure Date: 09/10/2022

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.

46 Engine And Engine Cooling problem

Failure Date: 09/06/2022

Car overheated. Check front engine and could not see any visible leaks. Check all around the engine and found coolant leaking from the back of the engine. Confirm by dealer that is leaking at the cylinder head.

47 Engine And Engine Cooling problem

Failure Date: 08/23/2022

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.

48 Engine And Engine Cooling problem

Failure Date: 08/22/2022

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.

49 Engine And Engine Cooling problem

Failure Date: 07/28/2022

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.

50 Engine And Engine Cooling problem

Failure Date: 06/30/2022

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.

51 Engine And Engine Cooling problem

Failure Date: 06/15/2022

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.

52 Engine And Engine Cooling problem

Failure Date: 05/13/2022

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.

53 Engine And Engine Cooling problem

Failure Date: 05/01/2022

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.

54 Engine And Engine Cooling problem

Failure Date: 04/21/2022

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.

55 Engine And Engine Cooling problem

Failure Date: 02/14/2022

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.

56 Engine And Engine Cooling problem

Failure Date: 12/09/2021

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 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.

57 Engine And Engine Cooling problem

Failure Date: 11/26/2021

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.

58 Engine And Engine Cooling problem

Failure Date: 10/27/2021

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.

59 Engine And Engine Cooling problem

Failure Date: 04/12/2021

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.

60 Engine And Engine Cooling problem

Failure Date: 07/30/2019

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.

61 Engine And Engine Cooling problem

Failure Date: 07/08/2019

Fails to accelerate and change gears. This has been happening since we purchased the vehicle. It has been back to the dealership multiple time and has not been resolved. They are unable to find anything wrong. The engine is a 2. 5 l turbo. This happens unexpectedly while driving making it hard to get on to the highway or change lanes.

62 Engine And Engine Cooling problem

Failure Date: 07/31/2018

This incident happened on 31st July, when my wife was driving this car on highway 4 martinez, CA at around 5. 00 pm with our daughter (2 years old) returning from daycare. She was driving at approx 60 mile/hr, when the car started giving audio visual warnings on multiple failures and the car started slowing down without responding to the gas pedal and engine propulsion reduced to 'zero'. My wife panicked and was luckily able to pull over on the curb side safely, even though traffic was very high. She stopped the car and turned off the engine and waited for 10 mins and restarted the car multiple times and made sure that no more warnings are displayed, before driving again, however the 'engine warning light' stayed on. After a while she drove home almost 40 miles away very carefully without using any cruise control. Here are the warnings, that came on during this failure, pictures attached. Engine malfunction light. Tire pressure indicator. Stability control indicator. Temperature indictor cruise control failure warning message �front radar sensor system malfunction� warning message �forward Smart city break malfunction� after a day we dropped the car to Mazda dealership for inspection and they found multiple failure codes and they did necessary repair (inspection and repair invoice attached). Even before this incident , we reported multiple times to dealership that the car central information system abruptly shuts down during drive. But they always said that there was no problem. This incident on a freeway was very serious, my family or other drivers could have been in a injury accident because of this issue with Mazda.

63 Engine And Engine Cooling problem

Failure Date: 06/05/2018

Driving to work in the morning at 5:45am on 06/05/2018 going 65 mph and my car cuts engine power and starts lowly declining pressing gas did nothing and multiple notifications flashing such as vehicle system malfunction, forward Smart city brake support malfunction, Smart brake system malfunction. I had to pull off to the side of the highway I can't even say I can pull off safely because all power was cut. So let the car sit for 5 minutes while off and then restarted and was able to make it work. I took pictures as everything was happening because I know the dealer ship will say something like "welp it ain't happening here so your car is fine. " I am very fortunate when I bought the car I decided to lease the vehicle so I can just take the car back. These malfunctions seem like a very severe problem and I do not want to hang on to the vehicle. Once 30k passes I will be super screwed! I called dealer ship and they are booked out 2 weeks so I cant even take the car in right away, plus they aren't even sure if they'll have a rental for me when I drop it off. Also to mention, ac unit already had to be replaced, and a suspension recall. Worse car I've had so far its sucks because Mazda used to be so great. Their service department sucks big time! I never had this type of service or issues this severe with my chevy. 08/07/2018 I took care in again for same situation along with ac and all Mazda tells me is they are looking into and assure me it will be taken care of this time. (also said last time) I think that they do not know how to fix the issue! I called corporate to ask for a refund and give the car back and all the told me was to give dealership another chance to fix the issue. It is so unsafe to drive and have kids in the car, I am very fortunate to not have my baby nephew and nieces with me when these things were happening.

64 Engine And Engine Cooling problem

Failure Date: 12/18/2017

Immediately upon making a sharp right turn into a parking spot, the car suddenly accelerated at a very fast pace without me pushing the gas pedal. My immediate reaction was to press on the brake, but it did not stop. The car slammed into a planter in front of me. The car moved so quickly that it was lodged into the bushes and had to be pulled out by a tow truck. I immediately called the dealer service department and told them what happened. The service manager's immediate reaction was to scoff at the idea that the car accelerated on it's own. My husband met me at the dealer and had subsequently found information about a recall of cx-9 models from 2012 for a similar malfunction. He showed it to the same manager who immediately knew the issue of the recall but was quick to mention it was the 2012 model, not the 2016. The dealer kept the car for a few days and told me it was driven twice and also some info from the computer was reviewed with Mazda tech support person. No data indicating any kind of malfunction in the car and the service guy did not have a problem with it in two short test drives, so they said come pick it up it's safe to drive. However, I will never drive this car again. This is the fully-loaded signature cx-9 that they feature in all their ads. I loved this car at first sight and drove it over 24000 miles in less than 2 years. This experience scared me to the point that I will never drive this or another Mazda again. I have had over a week to process this experience and am just happy my kids weren't in the car or that I didn't hit someone. I have found several other instances of sudden unintended acceleration online and cannot believe that this happens in 2017. I hope that this documentation helps someone else in my shoes feel that they are not crazy and this does happen. Shame on Mazda for not fully addressing this issue.



CX9 Service Bulletins
CX9 Safety Recalls
CX9 Defect Investigations