you bought it new?or just tried another one?you might want to check your cyl4 valves i worked on a guys car that kept throwing this code and when i pulled out his tempsensor it looked melted well we used one i new worked cleared up for 5mins i pulled it out same thing so i chacked his valves it was rocker had messed up and one valve was staying open just lil bit to long and the combustion creeped up