Plugs have approximately 40,000km and previous plugs we okay. Number #2,3,4 plugs look fine however #1 has alot of deposits on it. What can this be from? Possibly a bit of oil burning in that cylinder leaving ash deposits?

Thanks.

#1


#2


#3


#4

 

Try this page. Hopefully it will help. http://www.ngksparkplugs.com/t...2.asp

 

Thanks Ben... just as I initally thought. Now time to determine where the oil is coming from.