1997 Park Ave P0304 code present but runs fine

[Greg5150]

My 1997 Park Ave was sitting for a few days and when I started it up it ran rough for a few seconds and then ran fine and has run fine ever since. The check engine light came on when it ran rough on start up and has been on ever since. It is showing a P0304 code. However, the engine runs fine and I don't feel any miss. It runs fine at idle and under load. Any suggestions?

[DeltaP]

Check that #4 cyl plug,wire and coil. Erase code and see if it comes back. Check vacuum hoses as well.

[Greg5150]

Could I erase the code by disconnecting the battery for a while?

[DeltaP]

Yup.

[Greg5150]

Well, I put in a new set of plugs and now the check engine light is off. It was that simple.

[danielsatur]

If the problem ever come's back on cylinder 4, it's probably time for new spark plug wires, see
www.rockauto.com