4 cyl Camry near 100K miles on original plugs. Time to change?

[PontiacHO]

Harder on coil(s) when running plugs past their normal life cycle.

 

[willbur]

NGK might want to check with Honda on that. Best thing people can do when it comes to spark plugs and anti-seize is not tell anyone what they used or didn't use.

Exactly- Honda FSM says to and I saw AZ on the OE plugs when I changed them. Good advice about spreading that "knowledge".

 

[willbur]

Older plugs are harder on the coils, using more voltage to jump the gap, meaning the coil is more saturated and runs hotter. I wouldn't be in a panic, but if your keeping the car forever its time to change them.

I put back in whatever comes out myself, but if you want to upgrade feel free.

Odd observation, but I replaced great looking used plugs with new and it seems gas milage increased.

 

[2strokeNorthstar]

I don't have tons of experience but I've changed many factory-installed Iridium plugs in Hondas, Nissan, and even Ford that were 100k+ miles and they never looked that bad. If I had removed them for "inspection" only, I'd have left them in longer but they were all slightly past the service interval and I had the replacements so they were getting changed no matter what. The 6 plugs in a Nissan were still within factory-spec on the gap at 115k miles.

I agree, that's terrible for a modern vehicle. Even our Cadillac Northstar that burned a ton of oil had decent plugs at 150k. Changed them and noticed no difference. Our turbo DI Nissan had plugs that looked great and in spec at around 100k. I changed them anyway since I already had the parts and sacrificed the turbo inlet gasket to check them.

 

[Hall]

Exactly- Honda FSM says to and I saw AZ on the OE plugs when I changed them. Good advice about spreading that "knowledge".

If I think about it, I'll ask someone that has "hands-on" knowledge of Honda engine assembly

 

[Number_35]

I put those Rutheniums in our Honda Pilot, there have been no issues, it runs the same as always.

Same here, in a 2009 Mazda5.

 

[Number_35]

Agreed. Change em out with dealer OEM.

good run. For perspective, my old MOPAR with a 440 and 4bbl needed new Autolights at least every 6k miles. Of course they were only like $1.99 in the 90s

Back in the leaded-gasoline days, the debate (in my crowd) was over whether to change plugs at 10,000 miles or annually.

 

[KrisZ]

Wow, 4 pages whether it's worth changing 100k mile plugs.
Where is the "cheap insurance crowd" when you need them

 

[dumkid]

Same here, in a 2009 Mazda5.

Same here in a 2001 Mitsubishi Montero.

Plugs under the intake are fun to replace

 

[Number_35]

Same here in a 2001 Mitsubishi Montero.

Plugs under the intake are fun to replace

The frustrating things the ruthenium plugs came out shortly after I'd changed the plugs in the Kia Sedona (transverse DOHC V6), which involved pulling the intake manifold. That was a solid 4-1/2 hours for me.

I used ruthenium in the Mazda5 a few months later, but that's less than half an hour anyway.

 

[willbur]

If I think about it, I'll ask someone that has "hands-on" knowledge of Honda engine assembly

ppl need to understand NGK is recommending no AZ because the typical DIY customer will just slather AZ on the plug and overtorque. However, pro techs understand very little AZ is required and not to overtorque; hence Honda recommending AZ in its FSM, which is directed at pro techs. And used on the engine assembly line bc Honda has control over its application.
It's all about the anticipated customer.

 

[Kantaro]

BMW uses NGK in a lot of applications and their factory service manual says no antiseize:

• Do not grease/oil thread or use any graphite or copper grease. Adhere to the torque values of the packaging information or regulation.
  
  Note: If these instructions are not followed, especially with regard to greasing, this may result in mechanical damage to the spark plug housing/thread. Spark plugs that are not tightened sufficiently lead to leaks and to the spark plugs coming loose during engine operation."

 

[KrisZ]

All it takes is one stuck plug to change a simple maintenance into a repair of the head.

I’m sure BMW, other makers and even the spark plug manufacturers that don’t recommend antiseize will help you out with that no problem.

You can get away with using nothing on the plugs in very mild climates like CA, AZ, TX, but in places where it snows, good luck sticking with no antiseize.

 

[zzyzzx]

I'm surprised they've lasted that long. I've changed several of these 100K mile plugs before 100K miles because they didn't make it. My brother's Scion had 94,000 I think, and he drove it in on two cylinders and the OEM Denso plugs looked absolutely horrific that came out of it. Just changed plugs last weekend on the neighbors 2017 Dodge grand caravan at 76,000 because one of the OEM sparkplugs stopped firing. Changed sparkplugs on our 2008 Chrysler T&C at 75,000 as apart of a tune up when we got it, they were working but those sparkplugs were all fouled, half of them missing the double platinum pad on the ground strap and the gaps were all around .070" on those. Those were also OEM, my grandfather bought the thing new and never changed them.

Probably depends on how it's driven.

 

[dumkid]

If anti seize gets really hot the oil in it can carbon up and cause grief, but not as much greif as rust or the threads welding themselves together

 

[FordFETruck]

@zzyzzx Yep, the 100K mile interval is sort of misleading. If you do mostly highway or highway only you'll likely make it to 100K on the plugs, but lots of city driving or idling, forget it.

 

[michaelluscher]

Needs 4 NGK 96779 or Denso 3417 screwed in at this point

Just my option