help! i have an '07 mazda 3i & know NOTHING of cars. i've had the dealership check my report of "vibrations" or what i think are "waves" of vibrations three different times & they keep saying they can't find anything.
they replaced my engine mount & it did not improve.
i notice it when i am at a complete stop, but in "drive". recently it also seems more intense when my ac is on....
can anyone offer any suggestions? i am still under warranty & want to tell the dealer "FIX THIS" when i go back next month.
sincerely,
the girl who knows nothing.

 

the engine cooling fan turns on with the AC, and they are NEVER perfectly balanced. If you want to take it off you can balance it yourself. The fan is right in front of the engine, you can look and see it behind the radiator. Just don't get anything caught in there, like a finger or hair.
You can verify if this is the noise by leaving the engine on when you get home (done driving = engine is hot). Open the hood and listen & feel for any vibration, out your hands on the plastic where the hood latches shut, that's right near the fan. You'll hear when the fan comes on to know if that's what it is.
Also you can leave the AC on, it'll cycle on its own and you can hear the clutch engage and disengage with a click and associated 'loaded' sound at the engine. When the AC comes on the fan should turn on if it's off.

Good luck.

 

great, thanks!!! i will check tomorrow morning after my loooong drive work!
*fingers crossed*

 

It's either engine or tranny mounts. You said shakes when in gear do you mean when you stop at the light and sit there in gear it shakes? If yes, then indeed, all you did was suspension and brakes, it has nothing to do with it, when you are standing still but in gear, brake and suspension problems have no effect on the car. Check both engine and transmission mounts, if those are ok, its something inside your transmission.

 

Remember the days of the pagers? That's what it feels like when I'm at a light with my foot on the brake. And it feels like it's from under me. Was not the AC fan. That was completely still.

 

Right under you, like the seat / car is vibrating? That sounds more like the broken engine mount option. Which could also be some part of the exhaust hitting the floor or something of that sort.

If it's coming from the brake pedal it could be the ABS system - but in that case there should be a check engine light on as well.

Does it go away when you go to neutral? rev the engine a little? or only when the engine is turned off?

As for the dealer, if you can feel it, get a friend, make sure the passenger side can feel it. And simply tell the dealer that it's not just you, sit there in park and there's a vibration - and tell them to fix it. You may not know about cars, but if it's vibrating and shouldn't be - that's what the dealer is for.
If they say it's normal (which i've heard), tell them to demonstrate it with a new car for sale in the lot.

 

I had the same problem on my 2004 3i...had to take it to three places, including the dealer first, for someone to find the busted mount at my request. Told them to check those first, and sure enough. Take it somewhere else to have them check it and make sure it isn't the motor mount.

 

Motor mount guaranteed! I just went through the same thing. Had a front end knock FOREVER and though it had to do with the suspension. Turned out to be the top/passenger side mount. A week after changing that, the drivers side mount went, and my car felt like a harley davidson. The car vibrated like no tomorrow. Its more than likely your driver side mount. Good luck though, it was on backorder for like a month thru Mazda.