Idle-2500 RPM vibration

Like plugging holes in a dam, every time I fix an issue, another pops up.

During the last year:
I have had a passenger motor mount leak fluid, so I replaced it.
Then my battery needed replaced.
Next I cleaned my throttle body, which helped smooth out my vibration at idle and occasional RPM drop.

Then, this summer I started getting an idle to 2500 rpm vibration (high frequency) that would buzz the interior of the car. It is much worse when the car is cold. To try and fix this, I first replaced the rear motor mount, no change. Then the transmission mount and again, it didn't solve the problem. Last night I put in new spark plugs and did a 3 quart drain/fill on the transmission (Mazda fluid), still no change.

Has anyone else run into this issue before? It is quite annoying when my wife's 162k mile Mazda3 seems to be holding up better than my 81k mile Mazda5! I'm starting to wonder if I have a balance shaft issue, or cam phaser issue, but I have no check engine lights and gas mileage hasn't changed.

My old Fusion ate mounts like crazy. Our MZ5s are somewhat similar being from the same FoMoCo/Mazda generation. Click link for some pics of the carnage.

http://www.supermotors.net/registry/20962/73815

Unless I changed them all out every time the vibes remained.

I just started to notice our MZ5 shaking more than normal at start-up with 55k miles so we're going to be due soon, too.

torquelover said:

Unless I changed them all out every time the vibes remained.

Click to expand...

Understood, that was my gut feeling as well. I ordered 2 of the 3 OEM mounts this weekend (motor mount and rear mount) and will see what happens when those are replaced. If that makes a noticeable difference, I'll buy an OEM transmission mount too.

The dogbone or transmission mount made the most difference on my car.

Fixed!! It was the engine (passenger side) motor mount. It was a POS (from RockAuto) because it didn't even last a year, maybe not even 6 months. I put in an OEM mount and it feels like a new car. While an aftermarket mount may seem like a deal, and look the same, buy OEM for the passenger side mount.