I bought a 1997 Grand Prx gt and it blew up the next day. I put a new engine in it and now there is a problem. It runs like a champ when it is cold. It pulls hard and everything but then when it warms up it misfires and chuggs like crazy when its under load. It is reading out 2 codes. One is misfire in one or more cylinders and the other is a bad o2 sensor. The sensor was bad when my old engine was in and that one ran fine. Please help. I hope its something easy. Also my gas guage is screwing up. I dont know if that is due to the problem or not.
