Yesterday during my morning commute my car began to misfire and the check engine light began to blink. All signs point to not good, so I scanned the ECU and it returned P0304 as the error code, cylinder 4 misfire. So I took out the coil and spark plug and saw that it was fouled with oil in the spark plug tube and possibly in the cylinder too, but it could have been un-burnt fuel (in the cylinder).

Today I bought a new valve cover gasket set and took off the valve cover. Cylinder 4 definitely had a bad spark plug tube seal as it was torn in one spot. So I replaced the valve cover gasket and spark plug tube seals with new ones. I also replaced all 4 spark plugs. But unfortunately it seems this has not fixed the problem. I tried attaching the coil to a spark plug and grounding it to the block while the car was running and I did not see a spark anywhere, I also checked all of my fuses and they seem good.

Any suggestions?

Thanks a bunch.

My goal is to avoid this.

 

did you change the spark plug wires? or check the dizzy?

 

Posting a response when you apparently don't own this kind of car is not the most helpful. These cars do not have distributors or spark plug wires. As mentioned in my initial post, i used a coil (from a coil on plug ignition system) to test for spark.

 

Haha, my bad i forget to read subforums sometimes, so youve tested the ign coil?

 

ok your post says you did and you didnt see spark, why dont you replace the coil then?

 

After testing the suspected bad coil and an assumed good coil (on a connection presumed to work) it turns out I have a bad coil.