I have problem that I’ve noticed since I bought my Saab 900 equipped with the automatic transmission and am finally deciding to try to address it. Just to clarify, I’ve cleaned the filter, changed the fluid multiple times to freshen the ATF in the torque converter and it shifts really nicely, actually. The motor is smooth as silk, too. Here’s my problem: with the shifter in “D” at a stop sign or cross walk, and my foot on the brake pedal, the car vibrates strongly. In fact, it’s even popped my hood open on a couple occasions. However, if it’s idling in “P” there’s no vibrations that are out of the ordinary and it holds nicely to 900 RPM either way (I have recently cleaned the IAC valve).
Suspecting my brakes weren’t grabbing well, I recently replaced the accumulator on my ABS system and had the fluid flushed and refilled at a trusted independent import shop. It brakes great, so I don’t suspect it’s the brakes. Since the transmission, motor and brakes are great, I can only suspect the motor or transmission mounts, but that doesn’t explain to me why the problem would occur at specific times only. Has anyone had a similar experience or have suggestions on what to check? Thanks in advance, everyone!