[ericfox]

2002 highlander has been running in the "limp mode" / safety mode as my knock sensor is in process of being replaced here by myself... while I was at it I decided to replace the plugs... but they look a bit white to me... I have experience in powersports equipment... and I would say on a premix 2 stroke these would look lean... but I am not as good with cars, so I could use some other opinions please...

There are a few things to consider possibly:
1) car has been running in limp mode which I think retards the timing
2) have added a few containers of gum out and sea foam to gas tank in the past month
3) car has about 100,000 miles and these are original plugs as far as I know
4) have been running 93 octane for the past week... figured since the car was in limp mode it might be a good idea...
5) I have been resetting the problem code for the knock sensor for the past couple hundred miles which may change something since the knock sensor was not giving a good signal...

here are the pics
Thanks for any help!

 

[rty]

After 100,000 miles are the plugs supposed to look pretty? I'm not an expert but that's my 2 cents.

 

[TrailDust]

IMO those plugs exhibit generally normal wear. The whitish color is normal, but the worn ground electrodes and carbon deposits are probably responsible for some of the performance deficiencies you mentioned.

 

[falnfenix]

http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp

looks normal to me.

 

[ericfox]

cool.... thanks guys... I def feel better about the plugs now. Have a good day, eric

 

[REN69]

100k miles on the same plugs... time for new ones :yikes: I used to replace mine on the Corolla once a year.

 

[ericfox]

The dealer said they would have changed them at 80k... which prob is conservative... so 100k isnt prob that bad... they are expensive plugs... denso iridium I think... they prob last much much longer than standard plugs... either way once a year is way to frequent for plugs IMO... unless you just like doing it... on a highlander you have to remove the whole intake to get to the back 3... so I wont be replacing again until 200k

 

[outsider60]

The dealer said they would have changed them at 80k... which prob is conservative... so 100k isnt prob that bad... they are expensive plugs... denso iridium I think... they prob last much much longer than standard plugs... either way once a year is way to frequent for plugs IMO... to the back 3... so I wont be replacing again until 200k

The plugs look ok. Some have oil burnt off.... nothing major.
You don't need to remove the intake for the rear plugs. all you need is a swivel spark plug socket and a regular swivel. Take your time with the back ones.