Scoobyspanners

Pulled the plugs from the car Yesterday and found the Four porcelains coated in a light red layer of deposits. Brushed off easily with a copper wire brush. Did a Google search and found this indicated additive deposit fowling ( not a major problem apparently as most are non conductive ) . The thing is I do not use additives so what are Sainsburys adding to their super unleaded to cause this? Been Two Years since they have come out gaps were about 0.8MM so reset them to 0.65 MM. Other than that they were in an ok condition.Used to use BP ultimate but found the car liked the Sainsburys stuff better, cleaner idle and pick up with the supermarket unleaded............

Coffin Dodger

Shell V-Power does the same, as do most octane boosters. Not much to worry about by all accounts.

Scoobyspanners

Cheers!