Engine And Engine Cooling Problems of Mazda CX9 - part 1

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.

See all problems of the 2017 Mazda CX9 🔎.

Cracked cylinder head/leaking coolant.

See all problems of the 2018 Mazda CX9 🔎.

. In January 2024, I purchased a used 2018 Mazda cx-9. The vehicle ran well until [xxx], when I discovered an engine coolant leak. My mechanic diagnosed it as a known defect involving the cylinder head. My husband contacted Mazda customer service (cs), and they advised us to get an official diagnosis from a Mazda dealer. We brought the car to orland park Mazda, where a diagnostic confirmed the defect (report attached). We later received an email from Mazda cs saying that since our car was at the dealership, Mazda would take the lead in submitting the goodwill repair claim (email attached). When we followed up with orland park Mazda, they informed us that no one from Mazda cs had contacted them to authorize the repair. We relayed this to Mazda cs and gave them the direct number of our service advisor, adrian. Mazda cs said they would follow up and get back to us within 48–72 hours. On a follow-up call, I spoke with nancy at Mazda cs, who again told me that our case manager cindy would contact us within 48–72 hours. Instead, we received an email denying the repair, stating the vehicle exceeded the 120,000-mile limit for the extended warranty (our vehicle has 133,500 miles). While our car is outside the warranty period, this is a textbook case of a well-documented defect covered under tsbs for the 2018 cx-9. Mazda has previously approved goodwill engine replacements for other customers well beyond this mileage. We are seeking fairness and consistency in handling known product defects. Our request is that Mazda approve the engine repair under goodwill coverage as they have in many similar cases. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

The vehicle will hesitate/stall while driving down the road. The vehicle has done this multiple times and has actually shut off on 2 different occasions while at a stop. On 2 occasions now the vehicle has not wanted to start. I have taken vehicle to Mazda dealership and they can never duplicate it. When they check for any codes, the vehicle computer does not give accurate times when happened. This last date I took it to them 6/9/25, the computer said it happened 4000 miles ago. The time before, I took it in the morning it happened, 5 min after it happened and the computer said it happened 10 starts ago. The last time, 6/9/25 they said they suspect fuel pump going bad, but until the vehicle gives a "check engine" light or dies all together they are not 100% sure. The vehicle is unsafe if it dies in the middle of the freeway/road with no warning to myself or the other vehicles around me. This has been going on for at least 1 year now, maybe longer dealership has all records. Seeing how the 2018 & 2019 Mazda cx-9 had fuel pump recalls makes me wonder if the 2020 should have been included in this recall. This has been an on going problem. 6/7/25 was most recent incident.

See all problems of the 2020 Mazda CX9 🔎.

The vehicle was overheating and a message came up that power will be reduced. Then it would go away and come up every 3 minutes while driving. I brought it to the service center, we filled it up with coolant and the issue kept coming back this time with a lot of white smoke coming out at vehicle start up. My mechanic said this is a bigger issue most likely to do with a coolant leak at the cylinder head. There is a technical service bulletin but no recall as of yet.

My Mazda has been serviced regularly, in fact my next oil change isn't for 2,000 more miles. I was driving when I heard this weird noise. I looked at the dash and the oil light was flashing and the temperature was over heating. I could also feel the vehicle getting sluggish. I pulled over on the interstate. All the lights were on by this time. I popped the hood and there wasn't any coolant in the resivour anymore. I let the car cool down and I added some water as I was 1 mile from the exit where there was a gas station. I had to baby the car to the exit and shut it off whenever it got hot. The oil was full and seemed overfull even. . . . . Mechanic is guessing the coolant leaked if the engine. . . . I was stranded for hours with 4 children. . .

See all problems of the 2015 Mazda CX9 🔎.

Failed water pump, blown head gasket, major coolant leak, and warped head causing the vehicle to overheat and die when coming to a stop. Vehicle died when stopped in construction on a highway and we were nearly rear-ended. Vehicle never showed check engine light and temperature gauge never showed that vehicle was overheating but significant damage was caused to the engine from “excessive temperatures. ” failure of warning signals allowed us to continue driving the car with a significant engine issue. Now the entire engine needs replaced at only 83,000 miles. Car was diagnosed by licensed independent repair shop. Additionally, front struts went out at approximately 40,000 miles making the car wobble at higher speeds. Was inspected and replaced by dealership.

See all problems of the 2019 Mazda CX9 🔎.

Car coolant warning light came on for a short time 5 min after starting car, then would go off. During severely cold days it would come on then go off once the car was warm. On 2/25/25 the coolant warning light appeared and stayed on. The car made loud rickety noise, as it warmed up. After driving 2 miles the car coolant light turned red and began blinking. An alert appeared saying car over heating. The car was stopped and smoke came out of the car. The car leaked blue/greenish fluid. Overnight the car cooled. The next day the car continued making loud rickety noise driving to dealership. Dealership would not honor extended warranty for coolant leaks at the cylinder. The water pump cracked, with coolant leak also causing the cylinder to crack and leak oil. Dealership is suggesting total engine replacement. The car has gone through its normal servicing with no reported issues of coolant leak or depletion. The engine overheated in a span of 2 miles after being parked for 8 hours. The car was.

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.

Excessive oil consumption. In less than 3000 miles, I have to add a quart of oil.

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

Engine failure with crack in the engine after a loss of coolant fluid.

See all problems of the 2016 Mazda CX9 🔎.

Coolant leaking from engine block cracked cylinder head.

Our Mazda cx-9, having roughly 86,000 miles, had catastrophic engine failure while driving. This is caused by coolant leaking at the cylinder head and around the exhaust manifold. This in turn caused a crack in the engine block. Mazda refused to fix this as it wasn’t a “recall” and only a TSB sent out. 1000 of people have reported this issue, causing failure while driving but Mazda will not recall the engines nor fix them under an extended warranty. After a 4 month battle with Mazda they refused to fix this in our car even though they know the engine is a bad manufacturing issue. A recall needs to be made and Mazda needs held accountable. Our exact cause was exactly what the TSB stated but Mazda stated our crack was not in the correct spot. They need a recall covering all engine block cracks due to faulty manufacturing.

Coolant leaks at the cylinder head around the exhaust manifold. Caused crack in the head. The Mazda 2. 5t engine has this common issue that Mazda knows about. Mazda has a bulletin out but has not issued a recall. Car over heated and I was left stranded. Took car to mechanic who says I need to replace my entire engine.

Fan is not working and car is overheating when driving in traffic or low speeds - from forums this seems to be a common issue with this make/model and year.

Sudden and dramatic loss of engine coolant. Received a warning that engine was overheating, and to shut off engine. Quickly obeyed the prompt and found that most of the engine coolant had been lost due to a catastrophic failure of either the head gasket or head itself.

My vehicle was low on antifreeze. I brought it into the dealer and had them look at it. They told me there was an antifreeze leak inside the engine. I told them, I think there's a service bulletin on it. TSB-01-013-21 and there are updates to it. They told me that the antifreeze leak does not pertain to this service bulletin. I told them, how can that be? when it's an antifreeze leak with an engine that only has 66000 miles on it so far. I spoke to Mazda customer service in California they said the dealer is trying to get some financial relief for me to replace a $10000 engine. Which they said is on back order till March 2025. I said how can this leak not be a problem when the engine is on back order, I feel that this should not have happened with a engine, that has 66000 miles on it? and it should be fixed free of charge because antifreeze leak is a known problem with these engines since 2016, and they never notified me to bring it in and have the defective part fixed which causes the antifreeze leak. If they did that, my engine would not have blown and would not need replacement. I'm hoping they understand and do the right thing and fix this.

The contact owns a 2016 Mazda cx-9. The contact stated that while driving approximately 45-50 mph, the vehicle suddenly lost motive power with white smoke coming from the front of the vehicle. The contact was able to get to the side of the road to inspect the vehicle and became aware that there was coolant splattered all over the engine compartment. The failure had occurred twice. The “wrench” symbol was displayed with the “service vehicle” message displayed. The vehicle was taken to the dealer, who diagnosed that the coolant pump and water pump were leaking, and the radiator needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The manufacturer opened for the failure. The failure mileage was approximately 148,000.

Engine cylinder head is leaking coolant. This is a known issue by Mazda as they have submitted a TSB on the issue but have yet to submit a recall. The leak causes overheating along with pollution of coolant fluid into the environment. The problem was diagnosed by a Mazda dealership. The leaking occurred before a light came on the dashboard. The light on the dashboard only came on once the engine began overheating.

- my 2018 Mazda cx 9 started stalling and jittering at idle and then eventually during slow driving. - next day I got a check engine light, took to Mazda service center at the dealership I have been going to for last 6 years since I bought the car. - service center diagnosed that there was a coolant leak through the cylinder head which seems to have cracked. - further investigation indicated that this has been identified on many other similar Mazda engines and a technical service bulletin had been issued by Mazda to dealers. - on probing initially, dealership declined they were aware of any such problem. - the amount of repair for the engine replacement (cylinder head and other parts) is exuberant and is almost half of the value of my car, and is not expected for a low 44,000 miles car. - this had posed safety issue for my family since the stressed engine with leak in cylinder head could lead to fire and fatality. - I am awaiting response from dealership and Mazda corporation case#[xxx] for a response especially when this issue has been filed under a class action lawsuit: [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Head gasket leaking and caused major engine issue at 89,000 miles. Mazda has known of this issue, but refuses to recall it.

Over heating /coolant leak.

While my wife was driving her 2016 Mazda cx-9 grand touring on the freeway, many of the dashboard indicator lights came on warning her the engine was over heating and to pull over immediately. While she was attempting to move over to the shoulder, smoke appeared from underneath the engine hood which made it difficult to safely move over to the shoulder. She believed the car was on fire so immediately exited the vehicle along with her sister whom was pregnant. I arrived within minutes and noticed the engine compartment was smoking and coolant/engine oil leaking underneath the car. The car was towed to my local Mazda dealership where I was advised days later the engine needed to be replaced due to blown head gaskets. They advised the vehicle over heated causing oil and coolant leaking from cylinder head that is warped. This repair would cost $11, 179. 29. Mazda service advisor also mentioned the radiator and lower/upper radiator hoses needed to be replaced. This repair would cost $2691. 28. This incident could've resulted in serious injuries or death from a known issue with these engines by Mazda. It's only a matter of time before this failed engine turns into a fatality. Do the right thing Mazda and fix these engines. Your reputation is on the line.

Coolant leaks at cylinder head , Mazda of America knows issues but not willing to recall , they hava a bulletin number 01-002/23 . Pls help.

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.

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.

Cylinder head coolant leak. No warning lights.

While driving on an interstate service drive in michigan, my 2018 Mazda Cx9 gt suddenly lost power and began flashing overheating warnings. I tried to move my vehicle to a safe spot while the warning and sudden loss of power was happening, which took a moment due to traffic flow and my family being in the car. I moved the car off the road, and let it cool. I slowly drove the car to a parts store to get coolant. Once the cooling system was filled, I brought the car home and began researching the problem. According to internet threads like reddit this is a wide spread problem happening among Mazda vehicles with several law firms researching class action lawsuits. My car is stuck at the dealership until I can find $12,000 to fix it, and sadly there are hundreds more just like me according to sites like [xxx] and [xxx] [xxx] [xxx] [xxx] [xxx] [xxx] and includes a Mazda service bulletin which indicates that there are design faults in the original cylinder head that causes the issue and that repair techs should replace failed parts with the updated and redesigned cylinder head. [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Vehicle had bucking coming to a stop. Noticed coolant was l9w, and temp guage was fluctuating at a stop slightly. Brought it to lester glenn Mazda in toms river NJ, service writer informed us it is the cylinder head, and that the repair is approx $11,000. Vehicle only has 85000 miles on it, and was told by dealer that there is nothing they will do. This is a known issue, with a TSB issued in 2021 due to a defect in design where the turbo charger is mounted to the cylinder head. At this point, we are requesting the manufacturer take at least part of the responsibility of the poor design they sold to the open market, that is clearly a safety hazard to my wife and 4 kids, 1 of which is an infant.

We have a 2015 Mazda cx-9 touring with all-wheel drive (awd). The issue that has been happening is a flashing check engine light (cel) indicator showing up in the gauge cluster. This issue originally started in October of 2023. I was on the highway doing at least 55 miles per hour (mph). Before the light actually came on, I had already felt the vehicle shaking, and also noticed the acceleration was sluggish. In the blink of an eye, the cel came on and started flashing. After that point, the cel stayed on. I was able to get to my destination safely. We took the vehicle to a shop, and told the mechanics the issue, but they could not re-create what happened. We stopped driving the vehicle as much after this first encounter. A couple of months later, the issue still persisted, and we took it to another shop. They changed the spark plugs, and the vehicle had been driving cel-free for several months. Recently, we were going to take the vehicle out for a drive, and noticed the vehicle shaking (before the cel officially came on) again. The cel flashed and came on. As of this moment, the cel pops up and stays on when starting the vehicle. I put in a code reader, and the code that came up was “po304 cylinder 4 misfire detected. ” we are figuring out what our next plan(s) is/are with the vehicle. I looked at some forums for the 2007-2015 Mazda cx-9 generation, and I noticed that someone mentioned that there was an issue with the injector pigtail wire (one of the fuel injectors). They also mentioned spark plugs and coil plugs. But they still had an issue and it seemed to be not resolved. I'm wondering if this issue could have a direct or indirect connection with the takata airbag recall that was issued on August 13th, 2024 with a "do not drive" alert.

Approximately three weeks ago, a message on my dashboard said to pull over immediately. Your car is overheating. I pulled over to a nearby auto shop, which indicated that I was just low on coolant. They topped off the coolant, and everything appeared fine. Two weeks later, I got the same message on the dashboard, saying my car was overheating to pull over immediately. I pulled into a nearby auto parts store and purchased coolant for the vehicle. When I checked the reservoir, it was bone dry. I added coolant and drove the car home. The following day, I checked the reservoir to see if there was still coolant, but it was all gone. I scheduled an appointment with the Mazda dealer to have the car inspected. I also checked the Mazda forum website to see if other vehicles of my make and model had similar issues since I had never experienced this before. I found that the overheating in vehicles of my make and model was a "known issue" with Mazda. When I took it to the dealer the next day, the service agent informed me that the "known issue" was only with the turbo model. I explained that my vehicle is a turbo model. He said that Mazda did not have to cover any costs because no recall was issued, even though it is a known issue. Mazda is now refusing to cover the repair and has indicated that the repair and replacement of the engine will cost approximately $9800. If I had been alerted earlier, I would have been able to have the car repaired.

August 2nd I noticed a smell of coolant coming from my car. I looked under my car and noticed it leaking green coolant. I took it to Mazda where they had it for 7 days to then give me a $6,300 estimate with possible added expenses. They diagnosed it as a cracked cylinder head and needs a gasket as well. I am a single mother and have work but I cannot afford that repair especially since Mazda is not going to honor there vehicle and what they stand by. With this issue with the coolant leak and the cracked cylinder the vehicle could have overheated and go into limp mode and come to a sudden stop with my children in the car while driving on the road. I could be hit as this puts my family at risk of injury while we go to school or work. Mazda has done nothing but tell me to submit a claim with customer service which I have. I had my case manager call me once and left a voicemail and I have called multiple times and have not heard back. There was no warning of this until I found forums and other stories that this unfortunately has happened to hundreds of Mazda owners.

Engine is leaking coolant apparently due to a cracked engine block caused by a manufacturing defect in the casting. Mazda has a technical service bulletin, subject:leaks at cylinder head and the number is 01-013/21. But they refuse to help cover their mistakes and now we owners are stuck with replacing an entire engine out of pocket. Shame on Mazda.