05 Wrangler 4.0 P0431 Code!!
I just bought a 2005 TJ 4.0 42RLE trans. As I was driving home (approx 100 miles) the check engine light came on. P0431. I thought I could hear a exhaust leak before I made the trip home but was not sure. I crawled under the jeep and noticed the exhause was loose where it meets up with the manifold. I tightened the 4 bolts the best I could and cleared the code. The exhaust did not wiggle this time. After approx 100 more miles of driving the check engine light came on again. P0431. I can still hear what I think is an exhaust leak but only under acceleration. I know the p0431 can be a 02 sensor, a bad cat, or loose exhaust. The jeep only has 50k miles so I think the exhaust is still loose. Is there a trick to getting the bolts tight enough to seal the leak? Could it be the manifold?