What would cause white residue on my spark plugs? Im running very rich and have alot of carbon build up on the plugs as well, sometimes i will see a little bit of white as well. I heard its because of detonation, but my compression is perfect (just tested, about 118,118,118 front and 115,115,115 rear) Never heard detonation before.. running free flow exhaust and ~8 psi boost on s5 turbo with no FCD.

 

usually white plugs means that you're running lean

 

Lean, but not detonating? My car smells of fuel really heavily... but i guess that doesnt mean i am leaning outat higher RPM's. Besides getting a SAFC, is there any way to tell/ adjust?

 

Got a pic?
It could be residue from all the additives from the gasoline.


-Ted

 

most likely, glazing or a lean condition. Glazing due to intense heat and fuel on a new plug..attracting all of that fuel etc onto a new plug, IE..hot rodding a car with new plugs in it..

Dave.

 

additives or carbon/lean condition

detonation actually leaves no evidence on the plugs, it atually knocks carbon and everything out of the combustion chamber because it's nasty ****, lol.