Spark Plug Upgrade when-to

[dspace9]

Hi all I was wondering when people have replaced their 3 spark plugs in their Mirages, if at all?

Not even sure what the manufacturers recommended cycle for spark plugs is, but I am looking into replacing them in my Mirage preemptively.

I heard this could improve fuel economy, having optimal-shape spark plugs

[Eggman]

The consensus of reports from forum members seems to be that replacing spark plugs really isn't necessary. The factory plugs are pretty stout.

The service manual recommends replacing the spark plugs at 105,000 miles or 84 months.

What problem are you trying to address, dspace9?

[dspace9]

The consensus of reports from forum members seems to be that replacing spark plugs really isn't necessary. The factory plugs are pretty stout.

The service manual recommends replacing the spark plugs at 105,000 miles or 84 months.

What problem are you trying to address, dspace9?

Thanks, I'm trying to keep up with the recommended schedule of regular maintenance for my 2014 Mirage best I can and sits at around 70,000 miles right now, or 110,000kms here in Canada, and I have had the car like 70 months now.

Not addressing any specific issue, my Mirage is in the shop all weekend til Wednesday atm, just wouldn't mind maximizing fuel efficiency and engine's best possible performance.

[Eggman]

It's not a bad idea to take a look at them. Visual inspections can reveal problems - or, no problems at all. If you have a borescope camera, you could use this as an opportunity to inspect your combustion chambers and even do a simple compression test.

[dspace9]

you could use this as an opportunity to inspect your combustion chambers and even do a simple compression test.

I have a limited set of tools at home, and with my Mirage I try to keep things simple -- and just keep up with normal maintenance any car needs... and before anything gets bad, like my brake pads, that sort of thing.

New spark plugs for my Mirage won't hurt even if they have some wear left on them, none last forever.

I wish I did more of my own car work, maybe when I get my classic car, I will acquire more tools for working on cars.

[Scratchpaddy]

New spark plugs for my Mirage won't hurt even if they have some wear left on them, none last forever.

Modern iridium plugs, like the ones the Mirage comes with, come pretty close to lasting forever. It amazes me that they sit there in the heart of the engine, cracking out 15,000-volt sparks and enduring explosions thousands of times every minute, and they're only supposed to be replaced once or twice over the lifetime of the car.

Old-style copper plugs wear down like old candles over 10,000 miles or so, but iridium is darn near invincible. If you're not noticing any issues, or getting any codes, you're not going to see any improvement by replacing the plugs.

Then again, there are only three of them, so cost isn't too bad if you insist on replacing them anyway.

[Cobrajet]

I replaced my at about 97,000 miles. They didn't need it.

https://mirageforum.com/forum/showth...g-replacement!

[dspace9]

Then again, there are only three of them, so cost isn't too bad if you insist on replacing them anyway.

Spark plugs are inexpensive, but when you get your car serviced 100% of the work is not done by me, I look into costs for all jobs, if they're necessary, etc.

I am thinking super-long term ownership of my Mirage, so maybe if opportunity knocks to get a deal with other work being done to my Mirage this week, I might go for it, and replace the 3 spark plugs. True that it is at the heart of the motor, and takes lots of use

[dspace9]

I replaced my at about 97,000 miles. They didn't need it.

Thanks for the info! Sounds like Mirage's factory spark plugs last forever, I just wouldn't mind keeping up on some of the regular maintenance of my Mirage, even if it's "overkill" as they say.

[Mark]

Thanks for the info! Sounds like Mirage's factory spark plugs last forever, I just wouldn't mind keeping up on some of the regular maintenance of my Mirage, even if it's "overkill" as they say.

If you check them, it doesn't hurt to have a new set ready. If they don't look good, you all set to replace them. If the original plugs look good, you can keep the new plugs for another day. I would pull one plug. If you aren't having any issues & it looks good, I would assume the other two are ok. If not, you can surely go ahead & pull all three. Others are saying they still look good @ 100,000 miles.

There's no harm in checking them early, & being ready to replace them if necessary.

"NGK spark plugs are manufactured with a trivalent plating. The spark plugs display a silver or chrome finish on the threads. The trivalent plating reduces corrosion resistance from moisture and chemicals. The trivalent coating also acts as a release agent during spark plug removal. NGK spark plugs should be installed DRY, WITHOUT anti-seize.

NGK reports that tech support personnel have received a number of calls from installers who have over-tightened spark plugs because of the use of anti-seize. Anti-seize is a lubricant and affects torque values by up to 20 percent. If you use anti-seize against NGK recommendations, you MUST decrease the set torque on your torque wrench by that amount or risk breaking the spark plug, distorting the shell, or damaging cylinder head spark plug threads."

"Autolite does NOT recommend the use any type of anti seize lubricant when installing new Autolite spark plugs."

"AC spark plugs should be installed dry. Do NOT use any type of anti-seize lubricant on spark plug threads. Anti-seize lubricants decrease the amount of friction between the threads, resulting in over tightening."

"Champion spark plugs are zinc plated to reduce the chance of seizure in aluminum cylinder heads. Champion then applies Tin Tac” and ULTRASEAL’M coatings over the plating to further reduce corrosion and seizure. Anti-seize should NOT be applied to new Champion spark plugs."

If interested, this is the entire article on using anti-seize lubricants on plugs -

http://ricksfreeautorepairadvice.com...-plug-threads/

By the way - I would stick with factory equivalent NGK or Denso iridium plugs.