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Loose spark plug wire

I took a long trip this last weekend and before the return trip I checked the oil and realized I need some. I put two quarts which brought the level just about even with the top mark on the dipstick. the return trip was fine. Next morning I started the car and right away notice that the engine was misfiring. I checked the spark plugs and noticed that one of them was loose and had some oil in it. I checked the oil and now it showed the level to be well above the top mark on the dipstick. Could too much oil cause the spark plug to get dirty, get loose and misfire? This car is a 1997 and has 206,000 miles. This is the first time this has happened. Could the same thing happend with a 1999 Honda Civic?

Too much oil can cause some serious problems. However I overall, I would guess that you do not have a “spark plug” problem. It may well be several problems.

I would start by going out to your car now, hopefully after you have not driven it for say an hour.  Now check the oil level.  

If you have too much oil it [b] IS[/b] a problem.  

How dirty is the engine (the outside of the engine, not the inner workings)?  

There is something wrong with the oil thing.   You put in two quarts and it was even to the top of the mark.  The next day after a drive you had too much oil.   Something is wrong there.  

I suggest checking it again.  Without starting the engine check the level  Do the oil checks with the car on a level surface.  If your car is parked on a hill, that can cause a miss measurement. 

I would like to get a compress test of the engine.  You want to know what the compression is for each cylinder. You also should check the other fluids (transmission, coolant, etc.

If your sparkplug wires are not holding on to the end of the sparkplg tightly an apprasial of the wire set should be made. Just how old is this wire set? On a car like a 1997 Honda (4 or 6cyl) that indicates two quarts of oil is needed it should be verified just where this oil is going and perhaps don’t put two in all at once, put some in and check it after a bit of a short run. Something could certainly be “up” with a car that all of a sudden shows two quarts low.

If oil is sitting up in the valve cover and not returning to the oil pan it certainly would be prone to leak out and get on the outside of the plug. I think you have identified the cause of your misfire when you found your loose plug wire.

You probably need a new valve cover gasket set.

The spark plugs on your engine sit in spark plug wells in the valve covers. At the bottom of these wells are seals. If these seals start to leak, the engine crank case pressure can force oil past these seals filling the spark plug wells with oil. If the oil level gets high enough in a well, it will push the spark plug wire off the spark plug.

Also, if these seals are leaking and filling the wells with oil, and then the oil is checked shortly after the engine is turned off the oil level will be too low. Oil is then added to bring the oil level up to the proper level. Then as the engine sits for a long period of time, the oil sitting in the wells drains back into the crank case bringing the oil level too high on the dip stick.

The valve cover gasket set includes new seals for the wells that will stop oil from being forced into the wells.


Thank you all for your comments.
Since this morning I have replaced the oil and oil filter. the oil level is now correct.
I have also changed the spark plugs, the wires, and the valve cover gaskets. you were all correct in that oil did accumulate in the spark plugs wells. After I put the all think back together and start the engine, the engine runs smooth, however there is a hole on top on the valve cover that has a rubber seal but nothing to close it. I did not notice it before I took the cover off. Now when the engine is running it whistles and air is coming out. Did I break something? or does something needs to plug the hole?

Ok I found the breather hose that plugs into the top of the valve cover. I still get a bit of noise and now the engine light is on. As you can tell this is the first time I attempt an engine repair. When I replaced the gaskets around each of the spark plug openings I omitted the “O” ring and just replaced the gaskets as was in the previous installation. I assumed the “O” rings were with the kit only if needed. Should I have installed them also? Why the engine light? any clues?
Thank you all for the help.

Sounds like you are describing the place the PCV valve would go if your car is/was so equipped.

Overall, the descriptions of how cars are worked on seems par for the course. “Now what the hell is missing or wrong?” is heard all the time in the business. Valerio gets high marks for figuring it all out.

Thanks for the encouragement.
I reset the the engine light by disconnecting the battery for a few minutes.
If it doesn’t go back on by tomorrow, I should be all set and ready to tackle the Honda Civic.
Thank you all.

If your plugs show no evidence of oil collecting in the holes, then all is well. IF they do get oil in there, perhaps those “O” rings not being replaced is the reason. Generally if new parts come with a kit install them. The old “O” rings could be nicked, squashed, or damaged by removing and replacing. If they don’t leak, then leave them be. Keep those new “O” rings for awhile just in case you need them.

When/if that check engine light comes back on, go to a parts store like AutoZone and have the code pulled. Then post the code here, not their interpretation but the actual code. They will give you something that looks like a cash register tape and the code will be at the top.

The hole in the valve cover with the grommet around it at the center of the engine is for the PCV valve. The breather hose comes from a nipple in the valve cover at the end of the engine and goes to the intake duct.