Spark Plugs Question
11-04-10, 01:28 PM
#16
Lobuxracer addressed the notion you can tell "just by looking" if your plugs are good here:
https://www.clublexus.com/forums/5739716-post47.html
Whereas I've addressed the mathematical silliness of ignoring the factory recommendation elsewhere and will do so again.
The average person doesn't even keep a car for 60k miles anymore, let alone longer.... so he will never do this service at all... but lets pretend you keep yours for 200,000 miles... about 4 times longer than average... and about 15 years of ownership based on average miles driven per year.
If you follow the recommendation of the people who designed the car you will change them three times.
If you ignore those people because you're pretty sure the plugs look ok and run to 100k, you'lll change them twice.
That's a savings of about $400 over 15 years.
Or about half a tank of gas... per year... in savings... in hopes that you know better than the folks who built the car.
(and that's assuming you pay a dealer to change the plugs... do it yourself and you're saving about $5 a year ignoring the manual).
https://www.clublexus.com/forums/5739716-post47.html
FYI - for all the junior tuners out there - you can't tell jack about what kind of service life is left in a plug by looking at it. A bad plug can look perfectly normal and be worthless in service. There are machines which are capable of testing a plug under service conditions by applying pressure to the area where the gap is and measuring the voltage required to strike an arc. If you don't have access to tooling like this, you'll need to decide when to change based on either the factory's recommendation (required to meet emissions standards) or by keeping track of your gas mileage sufficiently to know when your engine is running significantly worse (with seasonal adjustment).
Whereas I've addressed the mathematical silliness of ignoring the factory recommendation elsewhere and will do so again.
The average person doesn't even keep a car for 60k miles anymore, let alone longer.... so he will never do this service at all... but lets pretend you keep yours for 200,000 miles... about 4 times longer than average... and about 15 years of ownership based on average miles driven per year.
If you follow the recommendation of the people who designed the car you will change them three times.
If you ignore those people because you're pretty sure the plugs look ok and run to 100k, you'lll change them twice.
That's a savings of about $400 over 15 years.
Or about half a tank of gas... per year... in savings... in hopes that you know better than the folks who built the car.
(and that's assuming you pay a dealer to change the plugs... do it yourself and you're saving about $5 a year ignoring the manual).
11-04-10, 01:30 PM
#17
Time has nothing to do with the change interval on spark plugs, just mileage...these iridium plugs are good for 120,000 miles in other engines, but in the direct injected motors the change interval is 60,000 miles...
The cost to change plugs is not much, and they are really easy to replace, so just follow the manual and replace every 60,000 miles...
The cost to change plugs is not much, and they are really easy to replace, so just follow the manual and replace every 60,000 miles...
11-04-10, 03:04 PM
#20
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I changed mine at 50k 'cause I was taking off the intake (IS250) anyway. While they are not $2 plugs, it's still cheap in my book.
The owner’s manual has a cliff note about the 60k interval. It states that the 60k interval is due to emissions standards. It leads me to believe that the plug may work for much longer then 60k BUT perhaps not at their best...
The owner’s manual has a cliff note about the 60k interval. It states that the 60k interval is due to emissions standards. It leads me to believe that the plug may work for much longer then 60k BUT perhaps not at their best...
12-20-10, 12:21 PM
#21
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Spark Plug Replacement IS 350
If you look carefully in the maintenance list changing the spark plugs at 60k or 72 months is required for the emission warranty which should mean catalytic converter, etc.
I have a lexus care extended warranty and don't want to risk something not being covered just to temporarily save $300.
My dealer wants $349 to do it but have estimates for $269 and $243.
If anyone has posted detailed directions and issues faced when doing this yourself please let me know as if they are charging that much labor it is either more complicated than most cars or just overestimated.
I have a lexus care extended warranty and don't want to risk something not being covered just to temporarily save $300.
My dealer wants $349 to do it but have estimates for $269 and $243.
If anyone has posted detailed directions and issues faced when doing this yourself please let me know as if they are charging that much labor it is either more complicated than most cars or just overestimated.
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