ok, i have a 91 civic si w/OBD0 b16a and awhile back code 8 was throwing until i converted into OBD1, new distributor, MSD cap, MSD SCI, etc problem solved...anyways been drving for awhile now and everything was ok, wasn't throwing any code...but untill the other day i've check and it was throwing code 8 again which is the TDC...WTF!!! why??