P0306 Cylinder 6 Misfire on 1996 Mazda Millenia

My check engine light went on. The diagnostic code is P0306 cylinder 6 misfire. The car seems to run smooth until after I've driven it for several miles, run an errand and start it up again. Then it starts to run rough. Is it a spark plug problem or something else?

by in Mililani, HI on May 15, 2011
Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
1 answer 1 comment
ANSWER by , May 15, 2011
It could be so many things it is impossible to guess without being able to drive the car experience the problem and do some basic tests. It could be a bad plug, bad plug wire, a vacuum leak at the intake manifold or intake runner, to much EGR being distributed to that cylinder, a clogged fuel injector and or other causes .A professional grade scan tool attached to the diagnostic socket under the dash would give lots of information that would help like looking at fuel trim figures to see if they are out of range and cylinder misfire count. If you wanted to cover the basics or learn more, Autozone have some popular workshop manuals for free on line once you register (for free) on their website http://bit.ly/autozone_repair_info. There is also a company that independent auto repair shops buy their information from that the same information inexpensively to do it yourselfers. The information is year make and model specific repair procedures, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate http://bit.ly/AllData_Repair_Manuals_Online
COMMENT by , May 15, 2011
Thank you for sharing your insight and information. The links you have provided will be helpful.