Recording of Engine Knock / Rattle Noise in new CX-9: Help Needed

Oh I live near Leesburg.

Good to hear that they seem to have a good service dept. My CX-9 will be 2 years old in July and I haven't been to the service dept yet.
 
Oh I live near Leesburg.

Good to hear that they seem to have a good service dept. My CX-9 will be 2 years old in July and I haven't been to the service dept yet.

Yeah, this was my first time going back to the dealership since buying the car in '08. I was definitely happy with the service I received.
 
I had something similar to Mx5+Cx9 where the engine was knocking only when cold. I started filling up with 93 and this solved the problem. I guess my car requires premium fuel.
 
There is a TSB for this now--TSB 01-035/10. The dealer will flash the ECU.

Apparently Mazda knows about detonation issues with CX-9s. They
are working on an engine controller update for it. Ron Tonkin is going
to let me know when it is available. It certainly would be nice if the
fix is just an easy simple flash for the ECU.

For now I am putting the car in manual mode and downshifting into
3rd for higher RPMs on the hill. That puts less load on the engine,
avoids whatever problem range the buggy ECU currently has, and
prevents the detonation.

Not the best news, but I am still hopeful.
 
Update:

Many of you have sent me PMs, so I thought I would provide an update.

I was very impressed with the response from Mazda Corporate. They sent two engineers from Japan to meet at my house and examine the vehicle. As previously mentioned, they also tested gasoline from several stations in my area. The engineers came on two separate trips and consulted engineers from Ford. The end result was an engine replacement and custom tuning so that the thermostat opens just before the start of going up the big hill. This was back in the summer of 2009.

Over two years later, and we have never had a problem with the new engine. I appreciated the support by Mazda Corporate and their response. I cannot say the same for my dealership, and I was glad Mazda had a mechanism in place that allowed me to talk to corporate directly without having to use our dealership as a go-between.

Hope this thread helps others and serves as a credit/testimony to Mazda for their customer support - thank you!

Last, as for my location, I live in Alabama, and BTW, my 1998 Mazda B4000 truck is still running strong with over 185,000 miles on it now.
 
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great timing on the thread bump..

i'm having this same problem with my 2011 cx9. amazing that after 3-4 years they still haven't fixed the problem, but i digress.

mine does not knock at all while cold, only when the engine is warned up. i noticed it a month or so after purchasing it new (in may last year), and when i took it in they tried to show me a TSB for a knock when cold, and that it was normal. i just got back from the dealer again and this time they tried lubing a couple things and tightening some stuff down (perhaps the brake booster mentioned previously here) but clearly they don't have a handle on what to do because his suggestion was to "use premium gas for now and see if that helps or not."

since i have to go back to the dealer in a few days once a part comes in (unrelated to this) i obliged but i'm not expecting the knock to go away at all.
 
Please do keep us posted. I've got a 2011 and mine seems to knock when warm as well. I just got back from my dealer and he also noted that the TSB is for cold knocking as well. They did the Brake Booster Nut fix and that didn't make much of a difference with my driveline droning that seem prevalent when the tranny goes into 4th gear under gentle load. For me it is noticeable in other gears but less and seems to be either an exhaust drone or a torque converter issue. It seems like other have similar issues as well. I will try out premium gas at my next fill up but that stinks since I wanted a car to be able to run on regular.
 
yeah, i'm not accepting that as a permanent solution. i'm going back wednesday morning to drop it off so they can have it and dig further as well as replace the other part i had ordered. the service manager is involved so they want to figure out the next course of action. i'll report back.
 
I'm having the knock issue. 2009 with 45k. It knocks when cold, regardless of hills or not. It knocks in the driveway when it's started up. It seems to go away when it warms up. It's getting dropped off at the dealer tomorrow. They were already telling me it's normal on the phone. The service writer said it was the aluminum intake not warmed up yet.....

Other than this issue, the CX-9 has been my favorite car I've owned. It hauls like a station wagon and drives like a sports car. I came from a 2000 Navigator to this.
 
Mazda engines have had noisy clacking when cold since the dawn of time, noisy cold lifters. This is nothing new AND IS NORMAL. What is not normal is any sort of knocking when warm / under accelleration.
 
It is like a small ticking sound when cold. This was the way my uncles subaru sounded. A lot of the older japanese cars 70's and 80's had this sound. It is normal i guess.
 
quick update on my issue: i finally got time and an appointment to go ride around with the service manager. we recreated the problem thankfully, but at the time he seemed to think it was some sort of PCV hose or something that was an issue (no clue, go figure). i threw out knock sensor as a possibility and he of course, quickly dismissed that idea. so today i go back and drop it off, because they wanted a couple days to "do some research" on what the fix should be. they had the car all day today when they thought initially it would be a half day job, and will have the car tomorrow too. i guess either their first idea didn't work or they can't figure out yet how to fix it. kind of annoying, but i want this resolved so i'm happy to keep driving the loaner 6 in the meantime.....
 
If it does end up being knock sensors.... they will rip the engine apart, put it back together, scratch their heads and then as a last resort, look at the knock sensors. This is how dealers operate.
 
apparently they found a leak in the brake booster when they were crawling around in there yesterday....so they said they will fix that for me. of course, still no progress on the engine noise. i think they're just buying time.
 
ugh. dealer called yesterday and said they had some regional tech or whatever come out and take a look. supposedly when he heard the knock he said, "oh yeah, this is normal! i have a cx9 and mine does this." so my response was, first, for a 35000 car this is unacceptable and two, i want the noise fixed. so they're now saying the only way to fix the noise is to replace the engine, so on monday afternoon i am going to go in and have a chat with these guys. i want the damn noise fixed, so if they have to replace the engine that's fine but we're going to talk about warranty coverage and all that jazz. i'm wondering if i can talk them into a buyback as well.
 
sts... if this is normal, than other 9's on the lot should make the same noise right? My 9 makes absolutely no knocking noise of ANY kind, except on cold startup sitting in the garage for the first 30 seconds or so, which is a Mazda trademark. All our MPV's growing up (we had 2 of them) did the same thing when cold, starting up. MPV's even ticked a little when driving around, but I've never heard any knocking noise in my 9 when driving. Not normal bro. Interestingly, I believe the MPV took 89 octane, and still ticked.
 
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