rough idle on 2002 Cadillac DeVille

4.6 noth star i change the plugs and wires crank sensors fuel filter code PO300 mutiple mis fire what else could this be

by in Ridgewood, NY on January 09, 2010
2 answers
ANSWER by on January 09, 2010
Here is a ton of great information about the P0300 code: http://repairpal.com/OBD-Code-P0300
ANSWER by on June 16, 2010
Try the Vacuum Hose's or Brake Booster.
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