Why Are Bosch Platinum Sparkplugs Bad?

[SquireOne]

What is bad about the bosch platinum spark plugs? I was just advised not to use them on my 1985 318i in another post, and so I did a search on the forum. Apparently this question was asked before, however it was not answered. Why are they bad? They are supposed to be better, right?

Also, NGK's, are they better than Bosch for BMW's?

[BMWJNKY]

They arn't bad plugs if the car came with plat plugs. Plat plugs were designed to be used with cars that have a hot ignition spark to keep the plat puck and eletrode clean. Using them in an older car that doesn't have a hot spark like the newer cars do will cause them to foul out and cause a poor running condition. If one of my cars came with plat plugs I would not hesitate to replace them with the Bosch ones when they needed to be replaced but neither of my cars came with them so I don't use them. At the BMW shop I work at I've seen plat plugs cause more running problems in the older cars than they solve. For your car just use the Bosch WR9DC or WR9DS if you use only premium gas.