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I recently purchased a very nice 2006 LS 430 and I'd like to do some of the regular maintenance myself. I've already changed the oil/filter (a first for me, went very smoothly) and, considering the mileage (128K), I was thinking about replacing the spark plugs.
I pulled one of the plugs (photos below) to see if I could assess their general condition. I've never done my own maintenance on automobiles, but have changed obviously worn/dirty spark plugs in lawn equipment and other small engines. That might not be a useful comparison, but I was surprised when I saw the condition of the LS 430 plug I removed, which I thought looked pretty good if it is the original plug with 128K miles on it!
I don't have full service records on the car, but based on its excellent condition, it's possible the plugs were changed before the required 120K interval. Carfax shows it was serviced very regularly at a Lexus dealership through the first 60K miles, but there is no indication of the spark plugs being replaced (no surprise at that mileage). I don't have service records after that because the second owner likely had the car serviced independently. The timing belt and water pump were replaced at 114K (per a service sticker under hood) and I can imagine the plugs possibly being changed along with that service. Or perhaps earlier.
I wonder if any of you with more experience look at the spark plug below and think, "It's very unlikely that plug has seen 128K miles of use."
Or, maybe my experience with lawn equipment isn't applicable... and you see those photos and think, "Oh my gosh, that plug is filthy and worn! Replace all of them immediately!"
I just don't have the experience to evaluate and was hoping some of you more seasoned hands might weigh in.
FWIW, I bought an OBD2 cable and have run a general diagnostic scan with Toyota Techstream. The car shows no misfiring. And it's running BEAUTIFULLY.
SOME QUESTIONS: If the condition of this plug is consistent with it being a replacement for the original (whether at 114K or earlier) what would be a good indicator that it is definitely time to change them? How crucial is this? If Techstream shows no misfires and gas mileage continues to be good, should I just leave well enough alone until something (what?) changes? Or perhaps I should just go ahead and change them all out as a preventative measure for peace of mind?
As a very busy dad, I'm never looking for an unnecessary job... but I also want to maintain this car well and drive it for a LONG time.
THANK YOU in advance for any advice you can offer!
here are my originals from July 2019 @ 118k. Looks like I didn't take pics close up. I remember thinking NGK means replaced but others here said no those are your originals
That's helpful, Johnhav430. While not as close up, your originals look to be in similar condition to the plug I inspected... at least to my eye.
I'd be VERY curious to know if there is a uniform opinion about whether the original factory-installed plugs on a 2006 LS 430 would necessarily have been one brand or the other (NGK vs. Denso). That might be a better determinant as to whether mine are the original plugs or not.
Thanks for your reply... and I hope others will weigh in.
original plugs will have a little "s" or "p" on the end, not visable in any of your pictures
My plug definitely has a "P" on the tip. It's not pictured but is certainly there. I assumed (perhaps wrongly) that meant "platinum"?
In any case, wouldn't the "P" be there no matter when the plugs were bought/installed? If I bought these same plugs today at an auto parts store, wouldn't the "P" be there?
As I said, there *is* a "P" on the tip of my spark plug. You stated that was the sign of an original plug. If that's true, great... all my questions are then answered. But I'm just wondering if that marking would also be on the same model of plugs sold commercially?
If anyone knows and could answer, that would be terrific. Thanks.
Those plugs definitely look like the originals. In any case, just replace them all and go another 100,000 miles without thinking about it. You will need to change them eventually, do it now.
would not an iridium plug have an "i" then. when I changed mine they has the "s" and johnny and you have "p". did you know that UL sold in Hawaii have no navagation? and some sold in south florida have no heated seats. huh. caint proove it but I'll bet ya a dollar.
I recently purchased a very nice 2006 LS 430 and I'd like to do some of the regular maintenance myself. I've already changed the oil/filter (a first for me, went very smoothly) and, considering the mileage (128K), I was thinking about replacing the spark plugs.
I pulled one of the plugs (photos below) to see if I could assess their general condition. I've never done my own maintenance on automobiles, but have changed obviously worn/dirty spark plugs in lawn equipment and other small engines. That might not be a useful comparison, but I was surprised when I saw the condition of the LS 430 plug I removed, which I thought looked pretty good if it is the original plug with 128K miles on it!
I don't have full service records on the car, but based on its excellent condition, it's possible the plugs were changed before the required 120K interval. Carfax shows it was serviced very regularly at a Lexus dealership through the first 60K miles, but there is no indication of the spark plugs being replaced (no surprise at that mileage). I don't have service records after that because the second owner likely had the car serviced independently. The timing belt and water pump were replaced at 114K (per a service sticker under hood) and I can imagine the plugs possibly being changed along with that service. Or perhaps earlier.
I wonder if any of you with more experience look at the spark plug below and think, "It's very unlikely that plug has seen 128K miles of use."
Or, maybe my experience with lawn equipment isn't applicable... and you see those photos and think, "Oh my gosh, that plug is filthy and worn! Replace all of them immediately!"
I just don't have the experience to evaluate and was hoping some of you more seasoned hands might weigh in.
FWIW, I bought an OBD2 cable and have run a general diagnostic scan with Toyota Techstream. The car shows no misfiring. And it's running BEAUTIFULLY.
SOME QUESTIONS: If the condition of this plug is consistent with it being a replacement for the original (whether at 114K or earlier) what would be a good indicator that it is definitely time to change them? How crucial is this? If Techstream shows no misfires and gas mileage continues to be good, should I just leave well enough alone until something (what?) changes? Or perhaps I should just go ahead and change them all out as a preventative measure for peace of mind?
As a very busy dad, I'm never looking for an unnecessary job... but I also want to maintain this car well and drive it for a LONG time.
THANK YOU in advance for any advice you can offer!
The "platinum tip" or disc on the ground strap and electrode appear worn...
11-09-20, 06:32 AM
Opinion: 128K miles on this spark plug?
