Ford Focus 1.6 Zetec (Another Problem)

Hi all
after just fixing one problem, theres another one rite after
her goes

first off the engine light is on constant on the dash (emissions)

1: speedo keeps going back to zero whenever it feels like it:frown:
2: heater a/c does'nt want to know:headshake
help please..

i know that its a 1999 with 163.000 miles on the clock but these zetec engines are meant to be the dogs bollocks...
or are they just a typical "FORD"
:mad::mad::mad: