1999 Dodge Avenger, 42,500 miles. I am the second owner. Just replaced the battery and on the way home from work i get the SERVICE ENGINE SOON light.. Code is P0300 but i have a smooth idle, VERY bad gas mileage tho..

42,350 miles, new battery and i am the second owner.. I just got 100 miles with 3/4 of a tank of gas.. On my way from work i got the SERVICE ENGINE SOON light and read the code. I got P0300.. Now i have a smooth idle, seems to drive fine, NEVER would have thought there was a misfire... I am stumped.. Any ideas?

Thanks!!

 

Clear the code and see if it comes back.

 

Ok, i wioll and i will let you all know what happens! Thanks again!

 

Ok, it came back on today.. Same code, not sure what to try next?? Anyone have any thoughts to as what it may be?? It is odd, runs and drives fine.. Bad gas mileage but you'd never know there was a miss..

 

Well the code came back on.. So i am not sure what to try next.. Very odd.. Runs and drives fine, you would never know there is a miss..

 

The light has come back on,,, Any ideas??