Why you should use the proper plugs

[mphudak]

Did a tune up on the 4runner last night in conjunction w/the valve cover gaskets. I was right @ 30K mark but figured i would do both at one time. When i pulled the plugs i found the previous owner had put in Iridium Plugs, Denso IK16's. When i pulled the first one I knew it was going to be interesting, as just looking at them you could tell how bad the wear on the gap was. When I was done i randomly grabbed one plug from each side. Passenger checked out at .051, drivers was .084!!!! (each side wear was similar) Needless to say it runs much happier w/the correct plugs. I owned jeeps for years, knowing that the 4.0 could eat plugs and it was happiest w/basic replacement plugs. Being this is my first yota, this was the worst i had ever seen.

For those that think premium/single electrode are OK...heres a what the iridiums looked like @ around 30K

 

[DocW8494]

Noted, thanks for the pics & PN#s

 

[Drcoffee]

Strangely, the whole point to using the iridium plugs is they are stronger and last longer. Those electrodes are just plain gone. I gave them a try last year but when my mpg dropped I replaced them with Denso double platinum/double electrode plugs.

 

[mphudak]

Funny thing was when i was researching plugs, one of the cheaper options was to just buy them directly from toyota. IIRC the plug were almost 1/2 price @ toyota vs web/local parts houses.

i'm anxious to see what my mpg is on this tank of gas w/new plugs. After the tune up, no leaky valve covers and 5100's frt/back and tundra coils it is a new ride. Now just needs a little detailing/cleaning.