Volvo Repair: replaced 1989 volvo engine with a rebuilt 1988 b-230, mass air flow, vacuum leaks

Question
replaced 1989 b-230 with a 1988 b-230 will not idle checked codes and temp sensor code came up replaced temp sensor computer shows no codes all coponents from 1989 are on this engine throttle positioning sensor checked ok, mass air flow code comes up when car idles rough and eventually stalls out. what advice can you give me any help is appriciated  

Answer
89 and 88 engine basically the same. Recheck all air hoses for vacuum leaks. If car was running before engine replacement then problem was installed during engine installation. Get wiring diagram to make sure the wiring connectors are at the right place.