Deep Humming Noise When Accelerating

CarComplaints.com Seal Of This Might Hurt

CarComplaints.com Notes: The only area of real concern for 2012 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 for most CX-9 owners, 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.

8.0

pretty bad
Typical Repair Cost:
No data
Average Mileage:
67,000 miles
Total Complaints:
1 complaints

Most Common Solutions:

  1. not sure (1 reports)
2012 Mazda CX-9 drivetrain problems

drivetrain problem

Find something helpful? Spread the word.
Get notified about new defects, investigations, recalls & lawsuits for the 2012 Mazda CX-9:

Unsubscribe any time. We don't sell/share your email.

2012 Mazda CX-9 Owner Comments

problem #1

Nov 032020

CX-9 Grand Touring 3.2L V6

  • Automatic transmission
  • 67,000 miles

A D V E R T I S E M E N T S

Took my 2012 CX-9 to the dealer for a deep humming/ rumbling sound when accelerating and over-all vibration. Dealer said the engine mounts were shot. I have a warranty on the engine and power train, so all I had to pay was $100 deductible (after I had to ask if the warranty covered what would have been an $1800 repair). Took the car home; having the same damn issue.

It's back at the dealer now and they are telling me I now need a new muffler (first they said catalytic converter then said "Oh, no, it's the muffler"). Not covered by warranty and $1200 to replace. I'm picking up my car and taking it to a muffler shop for a second estimate. I don't think this will solve the problem but I hope it does. 3 strikes and you're out in Florida.

- Kim S., Naples, US

Not what you are looking for?