I believe that he is wanting to use the vehicle PCM and not the donor PCM, which in that case, it will 100% have to be reprogrammed.codydaniels said:Your PCM does not have to be reprogrammed for it to run. It will run but once it has been installed into another vehicle it will most likely show the check engine light. If the express van had a security system it may or may not run. As far as reprogramming your PCM it can be sent to many people to be done. If you can get it running you can take it to a local shop that can do programming. You can use the harness from the other vehicle and cut and modify all day long until it is what you want but you should be fairly proficient at electrical before you consider doing that.