CarComplaints.com Notes: The only area of real concern for 2010 Mazda CX-9 owners is the brake booster.
In 2014, Mazda extended the warranty on the 2007-2013 CX-9 brake booster to 7 years / 90,000 miles. However this extended warranty has expired, so buyer beware.
This Mazda CX-9 brake booster failure isn't terrible in terms of repair cost — it "only" costs $550 average to fix. However it is a safety issue when the brake booster fails as it increases stopping distance. Owners have reported having to stomp on the brake pedal, & crashes/injuries have been reported due to this CX-9 brake booster defect.
While driving on the interstate, I accelerated while changing lanes. When I let off the gas (around 65mph) my continued to accelerate, reaching over 90mph. I applied the brakes to no avail, the pedal seemed to be locked in place and would only slow the car down to 80mph. I tried stomping the brakes but each time I took my foot off the pedal the car began to speed up. After navigating away from other cars I moved to the emergency lane and shut the car off. I lost power steering but was able to coast to an off ramp and park the car. In hindsight I should have shifted to neutral but I'll keep that in mind next time. I restarted the car after a few minutes of cool down, and the RPMs immediately jumped up, and the engine revved as if I was flooring the gas pedal. I shut the car back down and restarted again a few minutes after that, same result. After a 10 minute wait the car restarted properly, and I drove home (approx 7 miles). This is my first time experiencing this issue but have noticed in other instances when the RPMs reach 4k or higher, the transmission has trouble down shifting.
It gets caught and kind of hangs for a few seconds before reluctantly going back down.
A D V E R T I S E M E N T S
While driving on the interstate, I accelerated while changing lanes. When I let off the gas (around 65mph) my continued to accelerate, reaching over 90mph. I applied the brakes to no avail, the pedal seemed to be locked in place and would only slow the car down to 80mph. I tried stomping the brakes but each time I took my foot off the pedal the car began to speed up. After navigating away from other cars I moved to the emergency lane and shut the car off. I lost power steering but was able to coast to an off ramp and park the car. In hindsight I should have shifted to neutral but I'll keep that in mind next time. I restarted the car after a few minutes of cool down, and the RPMs immediately jumped up, and the engine revved as if I was flooring the gas pedal. I shut the car back down and restarted again a few minutes after that, same result. After a 10 minute wait the car restarted properly, and I drove home (approx 7 miles). This is my first time experiencing this issue but have noticed in other instances when the RPMs reach 4k or higher, the transmission has trouble down shifting.
It gets caught and kind of hangs for a few seconds before reluctantly going back down.
- richm., 757, VA, US