Iridium Spark Plugs

I went to my local Toyota dealer to purchase spark plugs for my 2002
4-cyl Camry. The parts guy asked how many miles I had - I told him 72K.
He said, "That vehicle has Iridium plugs - you should be good until 110-
115K miles."

Wow! I've never heard of a spark plug that could go that long. I guess
I don't mind paying $15 for each plug when they only have to be replaced
every 4-5 years!

--
DrWho

DrWho wrote:
> I went to my local Toyota dealer to purchase spark plugs for my 2002
> 4-cyl Camry. The parts guy asked how many miles I had - I told him
> 72K. He said, "That vehicle has Iridium plugs - you should be good
> until 110- 115K miles."
>
> Wow! I've never heard of a spark plug that could go that long. I
> guess I don't mind paying $15 for each plug when they only have to be
> replaced every 4-5 years!

1) leaving spark plugs in THAT long runs a high risk of the plugs seizing in
the head. Remove them slowly and use a little WD40.

2) another area of spark plug failure is the sealing compound between the
porcelain and the steel shell. Evidence of combustion leakage will be dark
brown "jet" marks on the porcelain where the porcelain meets the metal
casing.

--

- Philip

On Tue, 22 Feb 2005 19:53:23 -0500, a@b.com (DrWho) wrote:

>
>I went to my local Toyota dealer to purchase spark plugs for my 2002
>4-cyl Camry. The parts guy asked how many miles I had - I told him 72K.
>He said, "That vehicle has Iridium plugs - you should be good until 110-
>115K miles."
>
>Wow! I've never heard of a spark plug that could go that long. I guess
>I don't mind paying $15 for each plug when they only have to be replaced
>every 4-5 years!

The factory normally recommends to change them at 100k miles. I
suggest changing them at 80k for optimal performance.

In addition to longer life, iridium plugs normally have a performance
benefit too. This is mostly negligible on normally aspirated cars.
But, forcefed engines have proven to gain a few horsepowers and a few
pound-feet of torque with iridium plugs.