I recently bought a 08 Avenger 2.7L, check engine light came on shortly after I bought it (go figure). It was low on gas and I filled it with premium gas shortly after that the engine light came on. Had it reset to see if came back on with any other codes. It came back on same code. Reset it again. Put some seafoam in it for fun. Next time I put gas in and it went off. stayed off but now it’s on again...! Any advice besides replacing the cat conv?