Changing spark plugs in 2005 Tundra V8...advice needed

[sixdogs]

Thanks. I think I'm good to go since it runs like a top and idles smooth. Other than being a kid, this is the longest I've ever run a vehicle.

 

[dfkrug]

Modern plug gaps are wide, so these coils work hard from mile 1. As good as these
modern plugs are, they will erode a bit during their rated life - so by end-of-rated-life of these plugs, these COP coils are
working pretty hard.

That is why I monitor the gaps on my Iriduim plugs on my MR2. They were still nuts-on at 80K miles. I have never
had a coil-on-plug go bad on a Toyota I have owned or worked on (many). I have replaced the coil "cassette" on
a friend's Saab 9-5 Turbo. On that terrible model, you can only replace the 4 coils as a set, even if only one is bad.

Plug wires, OTOH, are pretty rare these days, and those DO get faulty after a lot of miles and years. Subaru was
one of the last major brand holdouts with a distributor (gone now). Any other new vehicles with a disti? My
own 04 Tacoma shares 3 coils with 6 cylinders, so it has HT wires, but no disti. The older Lexus V8s (similar to
Tundras maybe?) have a disti and very hard-to-access plug wires buried under panels and brackets. 10 y is
all you get out of those.

 

[aczlan]

Plug wires, OTOH, are pretty rare these days, and those DO get faulty after a lot of miles and years.

Its amazing what a difference a new set of plugs and wires makes... We recently replaced the plugs and wires on our '97 Dodge 1500 and the next tank went from 9mpg to 11mpg for the first time in the 7 years I have been around it.

Aaron Z

 

[3930dave]

That is why I monitor the gaps on my Iriduim plugs on my MR2. They were still nuts-on at 80K miles. I have never
had a coil-on-plug go bad on a Toyota I have owned or worked on (many). I have replaced the coil "cassette" on
a friend's Saab 9-5 Turbo. On that terrible model, you can only replace the 4 coils as a set, even if only one is bad.

Plug wires, OTOH, are pretty rare these days, and those DO get faulty after a lot of miles and years. Subaru was
one of the last major brand holdouts with a distributor (gone now). Any other new vehicles with a disti? My
own 04 Tacoma shares 3 coils with 6 cylinders, so it has HT wires, but no disti. The older Lexus V8s (similar to
Tundras maybe?) have a disti and very hard-to-access plug wires buried under panels and brackets. 10 y is
all you get out of those.

Toyoda does seem to use quality coils. A good COP design does work well.

Most on here get it already, but my comment was mostly a PSA re. not ignoring the engine OEMs plug change interval. In this geographic area (lots of long and ultra-long distance commuters), many people blow through even today's plug change intervals quick enough.

One of my points about COP designs (esp. 1 per plug) was that given the cost pressures in the industry, some manufacturers may be tempted to relax their coil specs....... esp. on a 6 or 8 cylinder, since it won't immediately cause an engine-stop situation.

Agreed though..... entropy always does win, regardless.

Rgds, D.

 

[3930dave]

Its amazing what a difference a new set of plugs and wires makes... We recently replaced the plugs and wires on our '97 Dodge 1500 and the next tank went from 9mpg to 11mpg for the first time in the 7 years I have been around it.

Aaron Z

More than once I've also been amazed at how badly eroded caps/rotors are, while still running.

Same deal here.... that increasing cap/rotor gap makes life more "challenging" for the single coil designs....

Rgds, D.