Another car joke

[John Hammer]

A computer salesman, a computer programmer and a computer repairman are 
riding in a car.  It has a flat.  

The salesman says:  We need a new Car, This one isn't working.

The Programmer says: No lets get out the manual and we will see what the 
problem is.  

The computer repairman says: no lets start switching the tires around and 
if the problem moves, we will know which one to replace.