If you have an automatic transmission, it probably has a forward clutch/band problem.
it will drive but when in reverse it wont move
A car that won't move when in reverse could indicate a problem with the transmission. It could also indicate a problem in the gear selector.
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why reverse wont go in on 2004 town car
Best guess, your Transmission is shot. You'll need to call a mechanic and tow it to the shop to get it checked out
For the Reverse problem, you could have low transmission fluid, or a bad transmission. For starting in drive, just about every modern car will not start when the transmission is in gear. They will only start in Park or Neutral. This is a safety feature to prevent the car from taking off into someone or something when started.
Drive...
transmission is gone.
crankshaft
Nothing... But it probably wont let you start it until you put it back in park.
Get new transmission
bad transmission