2016 Mazda CX-9

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.

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.

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.

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.

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.

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