O2 sensor problem

Sup guys been awhile since i posted on here... Ok heres the problem i just recently put a zc dohc motor in my 91 hatch... Its throwing and o2 sensor code so i put a new one in rest ecu and still throwing it.. i then checked wire for breaks and everything was fine... Now when i put a volt meter on there i think it was gettin to much volts.. Im running an 89 teg ecu... anything else i can check out please give me some advice and thanks in advance....

Is it the one after the cat? If so your cat might be worn out so its not filtering like it should. You could try a mechanical 02 sim, should cost about 5 bucks lemme know if you want to give it a shot.

only got one and its a 1 wire setup its right before the cat on my dp.. Mechanical?

ah gotcha. Its just not electric like the casper o2 sim and stuff, its a spark plug non-fouler, you drill out one put the o2 sensor in and screw the second non fouler onto the one that the o2 sensor is in and put it in the cat, it just makes it so the secondary 02 sensor gets less exhaust gas so it doesnt throw a code saying your cat doesnt work. But sorry i couldnt help ya out with this.

ok at least you tried my man thanks anyway.... I was thinking maybe fuel pressure might have something to do with it