Turbo Vacuum Regulator

My indestructable 1990 760 Turbo Wagon just started running like crap today, it would idle poorly then die with any load on the engine. I found a few suspect vacuum lines, especially the one to the fuel pressure regulator, and after replacing them it seems to be running better and is driveable, but not great. And now the check engine light is on. How do you read the codes ?? Is there a magic incantation that will cause the codes to blink out somewhere ?