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  • Bosch Platinum +4s with 70,000 miles

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 #148910  by grayslater
Many of us know that platinum plugs are suggested to be replaced every 100,000 miles. Unlike the average "Joe" many of us here too will not wait this long to replace them. I've read somewhere outside of the forums that the efficiency of the platinum plug is not as effective after 75,000 miles.

With winter around the corner, mpg reducing lately, and a curious nature of how my +4s have held up, I replaced the Bosch Platinum +4s in my 2000 with +2s last weekend. Taking more of an economical approach (with rebate offer), I opted for the +2s this time and compared results this week during my commute.

This time of the year the winds are blowing a little more frequently and the temperatures are dropping below optimal. MPG has dropped proportionate to the changing season over the past few weeks and the additon of new plugs made virtually no improvement.

I'm not sure how much of a difference there really is in the performance of the +4s compared to the +2s so I think I'll go the full 75K to my next spark plug change. :gulp Here's to the next 75,000 miles! Cheers!

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 #148916  by Bill Putney
In your looking at mileage for comparison purposes, don't forget the other factor that you have no control over: Seasonal fuel blends.