Carbon buildup on half of the sparkplug!

[jzak]

Hey Everybody!

So last time I replaced the spark plugs on my AMC 258 i6 / 4.2l , I noticed something weird. There was carbon buildup, but only on one side of the sparkplug. I looked online, but nobody seemed to have a real answer for what's causing it.

Thanks for any help!

Josh

 

[Hedgehog]

You haven't been turning your plugs around enough ....... ...... around enough ...... ohhh man I crack myself up something fierce ......

 

[hagar]

Yep.
You're supposed to rotate the spark plugs every 30,000 miles,

 

[mstar]

Valve stem seals are leaking.I have seen it many times.If your valve guides are also worn it may be time for a reconditioned head. Build up will be toward intake valve. Changing seals only would be a short term fix. mike

 

[Lumpy Grits]

What plugs are you using?
BTW-That is normal, if the carbon is DRY.
The carboned side is away from the exhaust valve.
LG

 

[mstar]

Yes I agree if the carbon is dry. What I was referring to was a oily buildup to the point of fouling the spark plug. I guess the OP will have to figure out that part.