Review on NGK 52004 FDZ081 Spark Plug by Brian Page

I had to replace my original kit because it came from the factory with the covers disconnected from the wires. That being said, Revain's customer service did a great job of helping me get a replacement set quickly and easily. In terms of performance, I noticed a slight improvement in fuel economy (I also added NGK iridium plugs) and a little smoother idling. Acceleration has also been slightly improved. Like the other reviewer, my cables were mislabeled, but a service manual or the internet makes it easy to work out which cable goes where. My guess is that the wire numbering is set up for multiple vehicles and the Explorer has the wrong end of the stick.