1996 850 B5202S engine oil/spark plugs

[PeteB]

I went to NAPA and was in a rush to get plugs for our 96 Non-turbo 850 and
they came up with an NGK 7092 BKR6EGP G-Power Plug that is a Platinum
plug. It seems too cheap at $2.79 ea:
https://www.ngk.com/product.aspx?zpid=9329

Seemed to run fine for about a year, now the idle is a bit rough, might need
to be blown out on the highway. Not sure if the plugs have anything to do
with the rough idle.