It's a 20year old petrol fiesta (I want it to eventually be a classic!) .It smells a bit rich but i don't know if this is a seperate problem. What should be my first steps...Should i check the head gasket? Timing? Thank you for your time - Paul

Optional Information:
1988 Ford fiesta 1100cc

Already Tried:
um, just serviced it and corrected the valve clearneces. Tried to adjust the alternater, btw, it idles a little bit erracticly and misses the odd beat. At higher revs there seems to be no problem