oops.. too late.. got the new TPS on and adjusted... got it from Oreilly Auto.. if i test the old one and it works fine do you think they will take it back?

According to our return policy, we are supposed to. But most people don't think we should, and will try to not follow it. I'd take it back and say that the resistance is off, that way you can just warranty it out and get your money back. Tell them you bought one from Napa already.