Engine Burning Oil problems of the 2007 Mazda CX-7

June 2014, I was driving vehicle out of town on vacation and it suddenly began running rough like the pistons were misfiring. Mileage was 69,700. I pulled into a dealership (1 mile away), dropped the keys, and called to explain in the morning. Later, they said they drove the car around the lot and the engine locked up. They took no responsibility for making it worse and charged me for confirming the loss of compression in the pistons. We replaced the engine at great expense and to a poor result. I found this 2007 model had a chronic problem with the variable valve timing (vvt) causing the timing chain to come out of adjustment and destroy the engine. Instead of issuing a recall and fixing it, Mazda offered an extended warranty to 6 years-60,000 miles. This is about the average point of failure, meaning half the people are not covered. A feature of the turbo charger is making the engine run hot, burning the oil, so people were often denied because the oil "had not been changed. " interestingly, Mazda said the timing chain had been replaced under warranty with a previous owner. That date and location coincided with a date of service shown on carfax for typical maintenance only. That dealership said they could not possibly do any work without it showing on carfax. I wonder who Mazda paid for the warranty claim. . . I want NHTSA to compel Mazda to compensate owners who experienced engine failure due to this documented design flaw.

I was experiencing a shake in the steering wheel at high speeds, which we attributed to a tire/wheel/alignment issue. I made an appointment when the check engine light came on. The dealership told me I needed the timing chain (and assorted peripherals) replaced. . . For the second time in two years. The first time was covered by warranty, but only after I produced the records to show the oil had been changed regularly. The second time was not covered under warranty. It cost $1500 to replace the entire assembly that was less than two years old. The dealership has recommended ignoring the manual on oil changes (every 7500 miles) and changing it every 3000 to hopefully catch any further issues. They said because the turbo runs very hot, it burns up the oil quickly. My car was very low when I took it in. They also said the check engine light will not go on due to low oil, but only for low oil pressure. The other issue I had was related to the rear view mirror. I have the auto-dim with compass, which was installed by the dealer when I bought the car. It has failed twice and been replaced under warranty. The second time was around 65k miles. Less than a month after my warranty ran out, the entire mirror fell off the windshield. In the early 2007 models, the clip that holds the mirror can not be replaced if it breaks. I had to have the entire windshield replaced in order to re-attach the mirror. I was told even though the mirror would have been covered since it had just been replaced, the windshield was not covered. That was another $250 to replace a perfectly good windshield just because the clip couldn't be fixed. I have seriously considered just trading this car in because I doubt very much it will be worth more than scrap value in a few more years.

2007 grand touring Mazda Cx-7 has well known vvt issue causing oil to burn, in spite of regular oil changes and all recommended maintenance. We are original owners and know how car was maintained . Timing chain went at 62k miles, just out of warranty. After that service, drove 1k more miles and noticed loss of acceleration. Took car back to dealer, and they advised we needed a whole new engine, which they would not cover, aside from a 20% goodwill offset. Spouse wont let me operate car any longer in fear it will break down causing accident. Unsafe vehicle.