I followed the recommendations as before and did the spark plug non-fouler trick to eliminate the cat. And just today after approximately 30,000+ miles without the cat the check engine light comes on. Any recommendations as to what I might check that all of a sudden made the light come on after all this time. Tomorrow I am going to check to see if it is not screwed in tight in the pipe, still plugged in, and what it looks like. When the light came on I was driving on a highway at 60-65mph and the air temp was about 50 degrees.

thanks for all the help.

 

No replies yet so I will post again to move it back up.

The car in question still has the problem. I had the code cleared and checked the O2 sensor, it had backed out a little so I tightened it back up and drove it for a week and tonight on my way home after I hit a bump the light came on again, and it is the same code. Anyone had trouble using the spark plug non-fouler trick or if someone used the spark plug non-fouler trick and it is working successfully on their car. I am just using one spark plug non-fouler because I got an old cat and just busted it out and exchanged it will my original cat.

thanks for all the help.