cha41i

It will cost around $400+ to replace those 6 plugs. So far, the car run smoothly no hick-up or mis-fire. Car start right up with in one crank of key turning. no bang noise like lawn mover. These plug set is an original that come with the car. But my mechanic recommend me to change it as a 100,000 mile maintenance. How do I know it time to replace those plug? Thank

salimshah

Recommended interval is 110k.

You can wait till you have a fail and then only replace the one that fails or replace them as part of recommended maintenance.

Check the DIY and shop around for better price but make sure you install recommended plugs Denso or NGKs. Dont bother with anything else, unless you have done your research.

Salim

bob2200

I waited until one of my coil packs in the back went bad, and then had the plugs changed at the same time. This was at around 130,000 miles, and the spark plugs looks fine.

hypervish

My plugs looked good at 160k miles. Not saying I recommend waiting that long, but I recall reading somewhere these are supposed to be good for 200k miles.

artbuc

Right. Denso presented a paper to the SAE showing the results of their successful effort to develop an iridium plug which would go 200k miles without any drop-off in performance in a passenger car. These are the fine tip plugs which are factory equipment in the RX's. They also make a larger tip plug which does not last nearly as long. However, not a good idea to leave plugs in that long because the threads could seize and do major damage when removing them. I like to pull them at 120k or so, inspect and re-install after applying anti-seize. I just pulled a set of NGK fine tipped iridium's from my niece's Acura TSX with 120k miles. I looked at the tips under magnification and they looked perfect...hard to distinguish new from used. Gap was perfect. For the vast majority of car owners, these plugs are good for the life of the car.

fastnoypi

fwiw,

Per advice of a an NGK engineer i correspond with on another forum, DO NOT use anti-seize on NGK plugs. They use chromium plating to prevent plugs from freezing into the head.
Denso is suspected to use the same chromium plating.

Anti-seize will also change the tightening torque..without enough care you can over-torque and strip the threads.

salimshah

Good luck getting a torque wrench on some of the spark plugs.

Salim

artbuc

The install instructions right on the NGK box say to apply anti-seize.

fastnoypi

got a pic? i've got 2 boxes of NGK iridiums here, no where on the box says to apply anti-seize nor off NGK's USA FAQ page.

fastnoypi

Its easy when you do it the FSM way of removing the intake manifold and using an extension.

Id buy a round of beers if somone can figure out how, using the forum reach around manifold method

artbuc

They were the laser iridiums #6994. The instructions also showed different torque angles for plugs with tapers vs plugs with gaskets.

fastnoypi

If you bought them legit or stole them is your business.

Just saying you probably "think" you saw instructions for anti-seize usage.
They are no where to be found on my new boxes of iridiums.

READ #1 on the attached NGK pdf link

NGK wouldn't spend the extra time, money and process to chromium plate the plugs..then tell customers to use anti-seize when it alters factory recommended torque specs.


source: http://www.ngksparkplugs.com/pdf/dyk_5points.pdf

Please Dont push the other person buttons. Salim

artbuc

I have been working on cars a long time and am well aware of the on-going debate re the use of anti-seize on plugs. That is why the label instructions jumped out at me. Maybe they were old stock boxes, who knows? But do not insinuate I am posting something that isn't true.



Guys: Please remain civil in public forum. I dont want to sit an wordsmith each note.

Enz

iTrader: (1)

Salamat for the link! Found this thread while researching wether to get Denso or NGK plugs for my 02 RX

fastnoypi

for OEM longevity get the NGK 4589 or OEM Denso 3297 Both have an iridium center electrode and platinum plated ground strap.
The NGK 3764 would also be a good candidate for 100k intervals with a slightly smaller iridium center electrode and standard nickel ground electrode. (saves you $3 per set of 6 if you're cheap )