I have a 03 EX-L with 104k miles on it. I've been having problem with the engine hesitating under high load, rather accelerating onto a highway or going up an incline, the engine would not want to go above 3000rpm. If I hit the gas a little harder it would actually start pinging. Recently it threw a o2 sensor low voltage code for the one in the front so I replaced it but it didn't alleviate the issue. A friend of mine suggest that it might be a battery issue in that it's not supplying a high enough voltage, so I went and have the battery checked, the battery was in fact needed to be replaced so I bought new one, but that still didn't resolve hesitation issue. Does anyone have an opinion on what the issue is?