2012 Mazda 3 - tin-can rattle at low gear acceleration?

[mazda604]

(1) Just bought a used 2012 with only 39,500 km from Mazda dealership. Within a week I started noticing a rattle that sounds like a tin-can from near the front-passenger wheel, mainly when the vehicle is accelerating from stop, but also when cruising at low speed and start accelerating again.

It's really disappointing because it sounds like a 15 year old Ford. Almost like the exhaust piping is rusted and has a hole; except once it hits the higher gears, it sounds like a normal engine again.

Any ideas? And I still have 2-years on powertrain, so might this be covered?


(2) Aside question: how do I tell if my Mazda 3 is a GS or GX? I don't see this information on the door, don't even think it's on the registration, and I'm pretty sure the sales staff kept interchanging these two model names. It's an automatic with cruise control, a/c, and the aluminum wheels.

Thanks

[sarujo]

What does it say on your insurance card/papers? Mine clearly indicates the make, year and trim. If you bought it from a "Mazda dealer", what does it say on the paperwork?

You could always ask @Jeff-TheBiz nicely while supplying him your VIN # and maybe he could look it up for you...

[Jeff-TheBiz]

I can also tell you the warranty start date.

[mazda604]

Hey, actually looked over paperwork, looks like it's a 2012 Mazda 3 GX. Is that the base model? If it's base, I was wondering how it ended up having cruise control, since I think the 2015 GX doesn't have cruise control.

[mazda604]

Eh, no edit option... service date was Aug. 2012, so I have two years left on powertrain, no other warranty though. Now I feel stupid that I didn't hassle them for at least 3 months bumper to bumper.

[staax]

Sounds like an exhaust leak, but its your tensioner pulley. Search for the tensioner pulley thread... I posted a video of the sound and spinning the tensioner pulley by hand reveals that the bearings sound shot.

Bring it to the dealer and they'll tell you nothing is wrong or just spray belt dressing which will ruin your belt in the long run.

Can get a replacement pulley for $8 off rockauto.

Also the 2012 GX can come with w convenience package which includes cruise. That or the PO installed cruise himself which is what a lot of us do including my self.

[mazda604]

Thanks. I saw that thread, but it seemed to be for older year models, so I wasn't sure if it applied to the 2012. I think there may be a couple threads on the issue too, can you give me link to the one which mentions the solution/fix?

[staax]

http://www.torontomazda3.ca/forum/sh...Gurgling-Noise

Same pulley on the 2.0l non Sky's for the first and second gen.... 2.0 sky is probably the same too but I don't have proof about that.

[mazda604]

I'm not sure if the gurgle is the issue in my case, because based on the videos on that thread, it seems to be present during idle. I think my case only applies when accelerating, pretty sure idle sounds normal.

But in that case, the solution was to replace the tensioner pulley as well as the belt, if I'm not mistaken? And that is near the front-passenger wheel, right?

I've booked it at the dealer for Friday. They said since I just bought the vehicle, they're willing to cover repair expenses, so I'm delighted with that.

[staax]

No, idle is normal for me.

I get the noise between 1500-2000 RPM, or in other words while holding the throttle at cruising speed.

Only replace the belt if it needs to be replaced, because you'll have to change the AC belt too to get a new drive belt on. At 40k, you won't need to.

The tensioner pulley is the highest pulley you'll see, so yes right next to the passenger side headlight... I believe its a 14mm bolt securing the pulley to the tensioner.

[mazda604]

Actually, I opened the hood yesterday and there is definitely some rattle when idle, doesn't sound like it is relaxed.

So I need to have them replace the pulley itself and not the belt.

I thought I read somewhere that the default belt wasn't the right dimensions, and that users replaced it with a different one altogether, and that helped with the problems; but maybe that was the pre-2010 models.