1997 Ford Contour 2.0 ztec motor POSSIBLE WRONG COMPUTER

Hello everyone!

This is kind of a crazy question but here goes.

I bought a 1997 ( 05/97 ) Ford Contour 2.0l ztec AUTO TRANS CALIFORNIA SMOG not multi fuel 150k miles vin# 3FALP6539WM107185

I bought this car with the check engine light on thinking it wouldn't be a big deal to fix because the car runs great and gets god fuel milage, boy was I wrong! It keeps flipping like 4-5 different codes one of them is PCM fail and the other is evr fail and egr fail
1401, 1409, 1390,1479. My mechanic thought this was weird because under the hood it has no EGR. The kid that owned it before worked at a wrecking yard so my mechanic suggested that perhaps to inspect the PCM so when I did it looked as if it was replaced. So now I don't know if this kid changed the PCM from a different car or what the hell he did. My question is this, Is there a way to verify I have the correct PCM in the vehicle? By the VIN maybe? I will clear the codes on this thing then start it up and 5 seconds later these codes are back. Any suggestions?

Yikes!