Oil in the plugs

[Popeye]

I started the car after 3 weeks of just being parked, it had developed a miss. I thought 'bad gas' and topped the tank without success.

I removed the plugs and found that the second plug from the front had oil in the plug well (as much as to cover the plug). I cleaned it and checked all the others and now the car is running fine.

Q: What would have caused one plug to have oil in the well? and none in the others.

Q: what needs to be changed to stop this issue?

Thx in advance

[cooljess76]

need to replace valve cover gasket and spark plug seals.
http://www.realoem.com/bmw/showparts...62&hg=11&fg=15

Part# 11121721876 $18.54 @getbmwparts.com
Part# 11121721476 x3 $1.48ea @getbmwparts.com
Part# 11121721475 $1.78 @getbmwparts.com

You should also replace the rubber grommets under the valve cover bolts Part# 11121721879 There's like 15 of them @ 0.82.

[dhong089]

Uh-oh...

This makes me worry as my car has been sitting for 1 month. How do you know if your car developed a miss? (what are the symptoms?) I'm hoping my car will not develop the same problems

[cooljess76]

Originally Posted by dhong089

Uh-oh...

This makes me worry as my car has been sitting for 1 month. How do you know if your car developed a miss? (what are the symptoms?) I'm hoping my car will not develop the same problems

I doubt the car sitting caused this issue. The seals just go bad after a while. An oil saturated spark plug wire will absolutely cause a misfire since oil is not dielectric and the current likely grounded out on the valve cover. As for knowing if your car is misfiring, you'll feel it with either a rough idle or sometimes the engine feels like it loses power momentarily. Some misfires are less obvious and can only be detected if you're sitting at idle and watching the tachometer. Some more significant misfires will trigger a check engine light and leave a misfire code stored in the cars computer.

[Popeye]

Originally Posted by cooljess76

need to replace valve cover gasket and spark plug seals.
http://www.realoem.com/bmw/showparts...62&hg=11&fg=15

Part# 11121721876 $18.54 @getbmwparts.com
Part# 11121721476 x3 $1.48ea @getbmwparts.com
Part# 11121721475 $1.78 @getbmwparts.com

You should also replace the rubber grommets under the valve cover bolts Part# 11121721879 There's like 15 of them @ 0.82.

Thanks for the advise, will look into it one of these long weekends.

[Monolith]

Add #12 to your list. It will most likely be hard and brittle.

12 Gasket 1 11-12-1-247-948 $3.67

[318ti_IL]

This is where my problems start long ago. After replacing this I had to replace ignition coil (not right away but about 2 months later car had hard start with shaking). Have no idea how is possible but mechanic says: "when oil was on spark plugs wires may pull oil to coil". Does it makes sense I have no idea but after wires and coil was replaced everything is fine. My friend has same situation with his Audi and his dealer give him same story about oil getting to coil thru wires. Is it possible ... not sure but be prepared.

[cooljess76]

Originally Posted by 318ti_IL

This is where my problems start long ago. After replacing this I had to replace ignition coil (not right away but about 2 months later car had hard start with shaking). Have no idea how is possible but mechanic says: "when oil was on spark plugs wires may pull oil to coil". Does it makes sense I have no idea but after wires and coil was replaced everything is fine. My friend has same situation with his Audi and his dealer give him same story about oil getting to coil thru wires. Is it possible ... not sure but be prepared.

I suppose that could happen in some sort of electrical gravitational phenomenon. However, I think it's more than likely that the plug wire being submerged in a pool of non-dielectric fluid such as motor oil, shorted out against the valve cover(spark plug wells) causing a misfire and over time fried the coil.

[UberWagen]

Don't be dumb and overtighten the valve cover bolts. HeliCoils are not fun.