Automatics use a flexplate, not a flywheel. Manual transmissions use a flywheel.
Flexplate is stamped steel piece with a ring gear welded to it (for starter to engage and start car).
Most likely one of the welds is cracked.
If flexplate comes apart, you can cause a lot of damage to trans and possibly crankshaft, so replace it.
Thursday, May 14th, 2009 AT 6:43 AM