checked my oil today and its over the full mark, would too much oil make my 94 sti smoke, thanks, phil.

 

Yes more than likely. Drain it down, it does not take to much oil to top up from Low to High about 1/2 litre if I remember correctly. If your dip stick has a small hole and a notch just above it, fill up to the hole when cold or top notch when hot. Just be careful when topping up.