I had a turbo car at one point and one of the ways to tell if the car was lean is when the spark plugs/or the blades on the turbo were white.

Im performing the 120K service on my is350 and the plugs have white powder like substance at the end. No check engine lights or anything. Car runs amazing. but whats with the white plugs.

I have attached a picture.

Thank you.

 

Well I can't find any logical explanation for this other than the previous owner never changed the plugs since the car was first purchased. These plugs have seen 110k miles.

 

Hmmmm, looks worse than lean...there's build-up on the plugs that leads me to believe there are deposits being left on your plug there. How do the tips of the electrodes look?

 

The electrodes look normal. It's the prongs that look destroyed. I'll post another picture with the electrodes as well

I do have that cam rattle upon starting which. Am I confusing that for knock ? I'm positive the car is not knocking.

What are the chances that during my last oil change too much oil was put into the motor. Any chance this could happen due to too much motor oil ?

 

Look at the other end of the plug.. do you see a yellow or white marking? If so, they are original plugs and have the full 120k miles on them. They are supposed to be changed at 60k.. and even at 60k, i see this when changing plugs. Seems to be fairly normal for this engine. If you arent using oil and have no codes, i wouldnt be concerned.

 

What do mean by " if you aren't using oil". I have no codes and as I said the car runs like a dream.

 

Meaning, you are burning through oil during oil interchanges...or "using oil."

I'm about to change my original plugs from late '05 on my '06 350. Got the new replacements sitting the garage. Hoping to not find similar plugs as you there.

 

I think my car is burning oil . I check oil levels often and sometimes have to add a little.

Best of luck to you ! Since I just did an oil change and new plugs I'm gonna monitor my oil level and pull my plugs after 2 weeks to see what's happening in there.

 

im guessing this is what you are talking about.....wow 120K and no spark plug change



Here is the electrode

 

Yea, that little marking means they are factory original plugs. Its also ok to "use" or burn a small amount of oil between oil changes.. Adding a quart or more between oil changes isnt something to worry about really..

 

^I would say a healthy motor broken-in properly shouldn't use up any oil. I've never had to add a drop of oil in my '06 350 since I've owned it back in April '11. Personally, if I had a motor that used (not leaked) a quart of oil in 5k miles I'd say it had a problem.

OP, throw in the new plugs and see what happens. I've read that those plugs can be good up to 100-120k miles, but I'm sure there's a reason why Lexus recommends it at the 60k interval.

Oh, I meant to ask earlier...were the plugs "wet" when you pulled them?

 

The threads on the plugs had traces of oil on them. The picture in the first post was taken right after I pulled the first two plugs.

 

Traces of oil on the threads is normal; an oil slick on the electrodes, is not normal.

Just monitor your motor's oil comsumption between oil changes, and that'll tell you how healthy the motor is. An unhealthy motor burning oil has excessive compression and oil control ring gaps, excessive piston-to-wall clearances, or excessive wear on the valve guides in the head. All not normal or known issues with the 350 motor. The 250 on the other hand...they have issues! LOL

If you want to dig deeper, a leak-down test could render you some facts about the motor health/compression.

 

Well I did the plugs and oil change this past weekend. I have a road trip coming up this Thursday, 800 miles in one day. I'll pull the plugs Friday afternoon, check the oil levels and report back.

 

^Have a safe trip!