I had to take my son's 1999 Ford Mustang from him as he wasn't making his payments (and the loan is in my name). Since he has both sets of keys, what can I do to change out the ignition so he can't just take it? What parts do I need and will it be very expensive. Thanks in advance for your help.

 

You'll need to reprogram the computer. The ignition lock, door locks, and trunk lock, mechanically, aren't too difficult. The computer is a different story. You'll have to go through a Ford dealership to reprogram keys, to the tune of probably $150 or so for each key (price will vary, of course).

I'd try snagging the keys from your son...Guido might be cheaper than a new lock set.