ok i changed out my old vats lock cylinder today with a new vats cylinder, i have the proper coded key for the new cylinder but when i plug the pigtail into the female connector under the dash it won't start, now someone before me used a resistor on the female part and the car starts no probs, any ideas why the key isn't working?

 

Did you get the new key made with a 'new' code, or with the old 'code'? Unless you changed out the VATS computer under the dash, you have to get the new key made with the old key's resistance - the VATS is looking for the resistance from the old key.

 

did that the resistance on the new key is the same as the old one, and the vats module is still original