2017 MAZDA CX-9 Engine Problems

I took our vehicle into Mazda due to a coolant leak that could not be located. It had my wife stranded due to the vehicle overheating. Everything lined up with CSP11. The dealership is now stating that the vehicle has a blown gasket and needs an engine replacement. This is the issue covered by CSP11 except that the crack is in the wrong location. They haven't found the Crack but are denying the warranty due to the covered location not being the source. The vehicle only has 93000 miles on it.

I was driving the vehicle on the highway when the vehicle started to overheat, lights started blinking, the car was smoking, losing power and acceleration. This car has a recall on the cyclindwr head which when cracks causing the car to loose coolant and oil. If it cracks while you’re driving especially on the highway the car will immediately loose coolant and oil thus causing a very dangerous driving condition. There was no indicator prior to the failure that there was anything wrong with the car. No check engine lights, no coolant lights nothing. Prior to this happening I smelled coolant in the car cabin , took it to my mechanic who tested the coolant system and found no leak. At the time he was unaware of the known issue these cars have with the cylinder head. The problem has been confirmed by Mazda and they notified me within the month of March of the problem and the extended warranty to replace the known manufacturer defect cylinder head. The Mazda dealer now has my car and acknowledges the cracked cylinder head caused the problem but said because I didn’t immediately stop on the highway and kept driving until I got to a safe location I was negligent and are refusing to fix the car which now has a blown engine, etc. it is available for inspection now at the Mazda dealer. My safety was put at risk because I could have died on the highway if the car completely stopped working, it was dangerous driving it when it first started happening because it started out of nowhere the car was fine I was driving 50+ mph and it started smoking, overheating etc. I could have also killed someone else. It is a disgrace that not only they won’t fix my car they want to say they won’t because I’m negligent? I drive my kids to and from school everyday do you think I’m going to risk their safety in an unsafe car? They should not only fix the car but compensate me for putting mine and my children’s lives at risk. A complete disgrace.

Vehicle experienced coolant leak also oil leak from rear of engine. Broken cylinder head due to turbo too close to head

My 2017 Mazda CX9 Signature Edition started leaking coolant from the engine near the firewall. I had a Mazda dealer investigate. They tell me the cylinder head is cracked and the entire engine needs replaced. This appears to be a common problem due to a design flaw and there is a Mazda service bulletin on it. I have found talk of a class action suit online because Mazda is not standing behind their product. I only have 88k miles on this car

My 2017 Mazda Cx9 was stalling and jerking while driving almost causing an accident but glad I was able to drive it home without causing an accident. Took the car to the dealership and was advised that it needs a new engine due to coolant leak. The coolant was going inside the vehicle.

The 2.5l turbo engine mounts are not manufactured strong enough to handle daily driving and torque under the weight of the turbo. This causing cracks in the block/head resulting in coolant leak, over heating, and full engine replacement.

July 10, 2024, antifreeze leaking from my engine leaking on garage floor. Yes, my safety was put at risk. July 12, 2024, local mechanic informs me that I have a cracked cylinder head coming from the back of the engine. July 15, 2024, vehicle will be towed to local Mazda dealership to have vehicle diagnosed. No warning lights, messages or any other symptoms of the problem prior to the failure. Happened July 10, 2024, at 3:50pm.

My Mazda 2017 CX 9 apparently had a coolant leak. When we had our oil changed, we were told it looked like it was leaking from behind the turbo booster. As I was driving it yesterday, the car slowed to an almost complete stop on the interstate and a warning sign on the screen showed that it was overheating to a dangerous level. I immediately pulled over and allowed the car to cool down. I checked the coolant level and it was not very low at all, although I did add some coolant at that time. It continued to overheat and even blew tons of smoke out through the exhaust, so I had AAA tow to my home. After researching this, I have found that there was a bulletin posted in 2021 from Mazda about this very thing happening. My husband thinks that we may have a cracked block or a blown head gasket due to this overheating. This obviously could have caused me to have a wreck on the interstate by my car overheating and shutting down so quickly. We are scheduling to have it towed to our local Mazda dealer to let him do the $99 diagnostic. Based on what he finds, which we think will be confirming what we think it is, we will have to have a new engine put in my car due to a defect in manufacturing from Mazda. Even though my car has 130,000 miles on it and is technically “out of warranty“, we feel this is simply unacceptable and that Mazda should help us with this most definitely. I have so enjoyed my Mazda, and I feel that this is not something of my doing, but rather a defect on Mazda part and it should be addressed.

This vehicle has been diagnosed as having the Cylinder Head Crack issue referenced in Mazda TSB 01-013/21. The car has just over 70,000 miles on it, so I understand it is out of Warranty, yet this issue only came up due to a known design flaw by Mazda. I have been told that I will be without the car for up to 9 weeks due to repair backlogs and the cost will be $5,250 plus tax!! This car has always been maintained at the Mazda dealership since purchase and has never had any other issues until this flaw, acknowledged by became an issue. Immediately, I brought it in, only to be told Mazda would not assist in a Good Faith repair. This is very sad that Mazda would do this to loyal customers, there should be a recall and this should not fall on customers pockets when we continue to give them business, trusting they would not knowingly put a full engine repair in their customers pockets

I noticed my 2017 CX-9 Touring was leaking coolant. It wasn't much but then checked the reservoir which is nearly empty. The car was overheating. I had it checked out by the dealer and initially I was told that it was bad radiator cap. This was fixed and resolved the initial overheating problems. The overheating issues resurfaced and took it a certified mechanic which indicated it was leaking from the engine block. The quote for repair was over $6000 See: Service Bulletin: 01-002/23

Engine head cracked and is still on car as of now. If engine overheats, engine can seize. The leak has been reproduced, but the head has not been removed for inspection yet. No warning lamps. A large puddle of coolant was noticed under the vehicle. From what I have heard is that the material is too thin and eventually cracks. There is a tsb that covers the issue, but since we've gone beyond the 5 yrs of the powertrain warranty it won't be covered. We are under the mileage limit. We lucky caught the leak before engine damage took place (as far as we know, since the teardown has not been performed. If the replacement head is "reinforcing" that area then a design flaw has been inferred and should be corrected to avoid serious injuries due to a seized motor.

My car has never had any issues but began burning through coolant. After analyzing myself and then bringing to a mechanic, it has a bad cylinder head leak. This is a design flaw in the motors of Mazda cars during the years of the models with a 2.5 Turbo motor. This flaw will now cost me over $6k for a car just out of warranty when I religiously serviced the car at the Mazda dealer I bought it at in 2017. I cannot afford these repairs that were cause by a design flaw on Mazdas side. There is a TSB and a class action lawsuit for this exact issue. Mazda should issue a recall or help owners pay for the repairs since they have acknowledged the issue but have not made it right.

I took my vehicle into the dealership service center to have maintenance and repairs done. I notified them to a coolant leak. They discovered that the engine has a cracked cylinder head and that the manufacturer is aware of the defect. They stated that they have new updated parts they will use for the repair so this will not happen again. At this time there is no Mazda warranty extension or recall that covers the cost of the repair.

There was a coolant leak on my Mazda CX9 Signature with a 2.5T engine, and when driving the engine temperature started increasing slightly before taking off and turning red. I had to pull off to the side of a busy interstate road very quickly and shut the vehicle down before it overheated any more. Once I got the vehicle to the dealership, they told me it was a cracked cylinder head leaking coolant, and that it was an extremely common problem for the 2.5T mazda engines around about 60k miles, and they were actively working on one in the shop where I was for the same problem. Mazda is not currently helping with engine swap or any repairs as a result and is sticking the customer with the bill.

Known issue in these CX-9’s. Had the issue fixed once with a brand new, Mazda, “redesigned engine.” 14 months and 30000 miles later it’s happening again. Leaking coolant due to cracked cylinder head. First repair was about 9 grand. This time my repair estimate since it’s premature was for another 6000 to replace the cylinder head versus the whole engine. That’s 15k on a used car when I could’ve almost paid it off with that amount at this point.

My car started leaking coolant around [XXX]. It did not gave me any alert the car was heating up. My eldest brother was the one that notices. I took the car to the dealership and they are telling me I need a new engine. Now I'm googling and I'm seeing a big number of people reporting same issue. The dealership refuses warranty because is up to 60k miles and mine has 72k miles. However many people are having same issue on where the metal in the cylinder head isn't strong enough to support the weight of the turbocharger. I'm seeing complain in the internet since 2016 and Mazda has done nothing to fix this issue. Please go to for reference: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

On 11/21/23 Mazda dealership informed that coolant leak in my Mazda CX-9 had ruined the engine. Research on the coolant leak has found several other cases in CX-9 models. It has been alleged that the engines in these vehicles may be prone to coolant leaks around the cylinder head and exhaust manifold joint due to excessive forces. When an engine coolant leak occurs, the vehicle may rapidly lose engine coolant and cause the engine to overheat. It has been further alleged that Mazda is aware of the engine coolant leak defect but has not extended the warranty or provided a redesigned part free of charge. As a result, consumers may be forced to pay for costly out-of-pocket engine repairs to correct the engine coolant leak defect.

I was driving to work with my daughter and my engine overheated out of nowhere and caused us to almost be rear ended

Leak from cylinder head caused by overheating. Reported a coolant leak prior to diagnosis. Car now shows an over heat code. Safety was put at risk due to immediate need to pull over and no longer able to drive the vehicle. Dealership and initial shop had different diagnosis of the vehicle. Shop advised of a head gasket leak only. Only warning maintenance light came on as car began to overheat. No earlier notice other than coolant leak seen on ground.

2017 Mazda CX-9 with crack in engine with coolant leaking out. Informed by mechanic that coolant was leaking out from the engine and was caught by heat shield. I smelled coolant, but never saw any on the ground. Per TSB 01-002/23 there is a crack that can develop in the engine due to stresses from the turbo/exhaust. A crack will develop near studs in the engine. Once crack develops, the coolant can leak out. However, in worst cases (which mine did not suffer from...yet), the coolant can leak into the engine and damage the internal components. Right now, I am looking at a $6254 repair bill to have a mechanic fix the engine. I will probably have to take this bill on as my family needs a second vehicle. Mazda needs to issue a recall that is the fault of their own, not the customer. This is occurring on too many vehicles, with turbos, from 2016-2020 CX-9s, CX-5s, and Mazda6s.

coolant leaks from cracked cylinder head which cause the car to overheat and have the engine stalled on the highway.

My car gave me a warning that it was overheating... and gave me a warning to pull to the side of the road because of safety and turn off my car engine because the engine is overheating. I was on the highway when this occurred. The engine coolant light was well into the red zone. I had my two kids in the car and my service animal... The car was say overheating and blinking the engine coolant red warning sign I brought the vehicle to a dealership and it was confirmed that my engine coolant was leaking behind the gasket head and is damaging the turbo charger. The same issue word for word that was stated in the TSB... Yes the warning sign of engine overheating and the engine coolant light to high flashing showed up on the vehicle and the warning of pulling over to a safe place to allow the car to cool down. I was on the interstate when the problem occurred. I also had to put coolant in the car because the reservoir was completely empty to take it to dealership for diagnostic assessment...I bought this car 6 months ago and it was running fine until 3 weeks ago. When the coolant continued to leak and the warning signs would not go away stating the engine was overheating. The repair for this known problem is astronomical and I'm wondering why Mazda has not sent a safety recall and why we are on the hook for the repairs when they know it's a manufacturer defect.

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.

Engine leaking coolant due to a cracked cylinder head. 55,000 miles on car. No indications of a problem other than odor. Problem was confirmed by an independent service center and dealer. Dealer says engine needs replaced.

Coolant Leak at Cylinder head. There is a known TBS01-013/21 They refused to pay for any of the cost to replace the engine. My out of pocket cost was $10K.

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.

Known engineering flaw that causes cylinder head to crack and leak coolant. Mazda will not do a recall even though numerous people are requiring new motors with no previous issues or warning lights on the car.

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.

Recently had my car into the local Madza dealer for oil change and break inspection. Soon after the oil change it started running rough. Then next thing I know it begins to overheat in the street at major intersection while driving home. Parked it let it cool down and then toed to Mazda dealer. Told antifreeze getting into the engine. I see Madza is aware of this issue and this engine is defective and can not handle turbo. I could have been killed at this very intersection so thankful I was safe. What if I was driving on the highway which I do every day this would have compromised many people's safety. This is a safety defect in that Mazda is knowing of this issue. The only warning was just as it happened. except it was riding a little rough at stops but no idea it was going to overheat. especially since it was just in the shop for the oil change. My car is still sitting at the dealer as they try to get warranty to cover. I could have been killed. When will something be done to protect the consumer.

Coolant leak from a cracked cylinder head that mazda is aware of and released a TSB about. Refusing to extend warranty or fix due to being 6 months out of 60 month power train warranty. Still under 60,000 miles.

This problem has been documented and know by Mazda for awhile. They are aware that their 2.5 Turbo liter engine has the problem of cracking the cylinder head due to some overweight of the same engine component. My Mazda local dealer already inspected the car and told me that the fix is replacing the whole cylinder head, which with them would cost me 3.5k. My warranty company, which I purchased when buying this used car, didn’t took responsibility of the repair cost because it was pre existing condition before I bought the car. Many people over the internet have reported this same issue happening to them, models year between 2016-2019. This issue cause a leaking of coolant. Which in my case has been a lot built up, to the point that you can grab it with your hands (the coolant residual).

Coolant leak. Cracked cylinder head in a stud hole of the exhaust manifold. 70,000 miles Seems to be a problem with many other owners.

The first sign of an issue was an oil pressure indicator on the dashboard, but upon inspection, the oil levels seemed completely normal. The dashboard light went away shortly after that. A day later, I was on my lunch break and parked my car in a garage for 45 minutes. On the drive there, I did not notice any issues and was able to operate the vehicle fine for the short distance that I drove. When I returned to my parked car, there was a large puddle of oil underneath. I immediately had a mechanic take a look at the car. The mechanic was able to identify a cracked cylinder head, which led to water and coolant entering the engine. He highly suspects that this caused a blown head gasket in the car as well. As well as that, the car's starter, which worked just fine on day 1 of the issue and has never had any problems before, has totally ceased function. If I had not noticed the oil pool underneath the car and driven back to work as usual, it could have caused the engine to seize and create a very dangerous situation for myself and others on the road, including but not limited to the potential of an engine fire with the level of oil lost. The car was up to date on its servicing, including oil changes. Two ASE certified mechanics have inspected the vehicle and confirmed the leaked fluids and aforementioned issues. No other professionals inspected the vehicle (insurance representatives, law enforcement, etc.).

Vehicle has only 50k miles and developed a coolant leak which was caused by a crack in the cylinder head. No check engine light or overheating, but this repair will cost was estimated as over $4k. A cracked cylinder head would eventually lead to vehicle overheating which can put driver and passengers in a dangerous situation if vehicle were to overheat while operating as this is a significant engine repair. After dealer technician inspected the part, I was informed that they don't see overheating or poor maintenance as the cause of this issue, but it was caused by the part failing.

Technician noticed coolant leak around turbo during routine maintenance. Sometimes after long drives we would smell hot coolant but didn't think it was an issue. Dealership took it in for repair under power train warranty and was advised that the engine needs to be replaced. From my understanding, the turbo is too heavy for the engine and has caused it to warp. The coolant leak is a symptom of a damaged engine block.

What component or system failed or malfunctioned, and is it available for inspection upon request? Cylinder head has cracked and the vehicle leaked coolant and overheated while driving leading to engine failure. Vehicle is available for inspection How was your safety or the safety of others put at risk? Car overheated while driving leading to engine failure Has the problem been reproduced or confirmed by a dealer or independent service center? Dealer has diagnosed the problem as a cracked cylinder head Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes, dealer has diagnosed issue and recommended replacement Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Engine temperature sensor went off and within seconds car was not driveable due to fluid loss

Engine has serious manufacturing defects and a recall should recalled. The engine has casting issues which cause internal issues.

2017 Mazda CX 9 signature engine failure at 89,000 miles. July 2021 check engine light came on, this was three months prior to failure. Was told it was a known computer issue and was charged over $200 to fix. November 2021 car started running hot while driving down the road. Red thermostat came on while driving. Was able to get the vehicle to the Mazda dealer that has done routine service on the vehicle. Was told it needed a new engine. Called Mazda customer service and was told it is a known issue with the turbo charge engine. This is a safety risk to myself and others because it could have gave out in traffic.