well, i replaced my spark plugs today, i used just some regular ac delco's. but when i pulled out the old ones, i had one that was fuel fouled, im wondering if my new one will foul out aswell? im replacing my O2 sensor tommorow. but is there any adjustment or is something wrong that could have caused the old plug to foul, and possibly the new one? thanks.

 

could of been any number of reasons. making sure you tune up is good and sensors are working correctly would be a good start

 

Check the plug wire going to the cylinder that had the fouled plug as well....