Two problems related to vehicle shudder have been reported for the 1997 Mazda 626. The most recently reported issues are listed below.
I noticed my car shaking at idle and when I put it in park. I also noticed a puddle under my car so I took it to get looked at right away. On the way to the service station it would not shift. All symptoms I have heard on this site, but no dealer ever told me of any problem. Now the car is not worth the price of a new transmission and I am without a vehicle. Would have been nice to know that there was a problem with it.
When the gear shift is in drive, and the brake is pressed, the car shakes violently and so much that it actually creates a humming noise. The vibration is so intense that it cause ears to clog up. Took car to browns mazad dealership, because still under warranty. Was told it was the motor mounts. They had my car for a total of two weeks, waiting on a "part" which happend to be a bolt and when I pick up the car, it was in worse condition than when I brough it in. I was told that the some vibration is normal, but I am literally shaking when the car idles in the drive gear. Nasty attitude. I am still covered under warranty and I asked to have the mounts replaced, but was told it was within 'specs' therefore, live with it. This could become a potential safety hazard, because I have to put the car in neutral gear to stop the shaking.