I've been dealing with a wonky O2 sensor in my 98 Civic for a while now. Around town driving is ok, but as soon as I hit the highway it starts to act up. It'll feel like it's running out of gas and my Ultragauge will show the short term fuel trim at -29.7, but as soon as I take it out of closed loop operation (either flooring it or getting off the throttle completely) it runs like normal. It'll also work fine if I just unplug the O2 sensor. I've been pricing O2 sensors online and I found a cheap aftermarket one from Primechoiceautoparts for a bit over 28 bucks, and I've found Denso branded O2 sensors on eBay for 48 bucks. Which one should I get? Would the aftermarket one be ok or should I just go with the Denso branded one?