willfxp

I bought my IS at 75k miles. Wasn't in the best of conditions, so doing a lot of preventative maintenance work. The dealership said they _think_ I still have original plugs because there _was_ a misfire logged in the computer some time ago for #1 (and IIRC) #3. They couldn't tell me when, of course. But right now, I have no problems at all with performance. I floor it and it feels just fine to me.

So I go to replace my plug just in case, and I pop the plug on the right out (yeah, the one on the left is brand new for reference). Just wondering if this looks like a plug with 75k miles or 15k. Or maybe I should just replace it anyways, even though I don't look forward to taking off the intake manifold.

Thanks!

accelerate

O yea those are looking original, I replaced mines at 70000 and they looked better than those.

NastyIS

iTrader: (1)

Yep, my guess would be the one on the right is an original. No question that it's far more than 15K.

Slammer1

Original plug on the right, for sure! You should see a nice increase in performance after changing them.

06isDriver

yeah, looks like the spark gap got real wide on your original plugs. The electrodes are just eaten away.

willfxp

Awesome. Thanks for the help. It was just one of those "is the dealership trying to get money when everything feels ok?" kind of things.

chi123

iTrader: (12)

All my spark plugs looked like that at 51,000 when I replaced them myself. A few even had oil on them.

OPTiK

That's not good!

new.era.13

iTrader: (10)

these spark plugs are ment to last 100k, but on all the lexus, they barely last to 60k.

Kurtz

iTrader: (1)

The owners manual says 60k. I'm not sure why folks keep thinking they can wait 100k between changes.

Sffd103

iTrader: (16)

I was even told that by a Lexus mechanic here on the forum that I know.