I think it's time

"Full of the sound of the Gran Fury, signifying nothing." (granfury)
04/17/2018 at 17:04 • Filed to: None

Although they’re supposed to be good for 100K miles, it’s probably time to change my plugs after about half that time. I no longer have a long commute, so it would make sense that normal wear items would need replacing sooner due to the increased stresses of 95% city driving. Thankfully replacing them on the Mazda5 is an easy task, unlike the ol’ Windscar where you could only reach the rear bank of cylinders from below.

So, are there any differences in spark plugs these days? Any favorites out there? I used to be partial to the expensive Bosch Silver plugs, but that was 30 years ago and I’m sure things have changed in the last few decades.

DISCUSSION (13)

crowmolly > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:21

NGK seems to be one of the better brands.

Highlander-Datsuns are Forever > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:25

My mazda 3 uses irridums, had to order them from Amazon. Napa didn’t have them in stock. They have been on my shop bench for three weeks waiting for me to do the change out. Looks pretty easy from what I can tell. It’s just the car is 12 years old and has 70k with the original plugs. Hope they come out.

Highlander-Datsuns are Forever > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:25

https://www.amazon.com/gp/product/B00VHVHEK0/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

yitznewton > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:27

I just did the Prius last week, with OEM plugs. Sooo much easier (transverse I4) than the Ford V6 I attempted years ago, and the Toyota V6 (Sienna) which I didn’t even bother trying.

My plugs came right out, no sweat. The PCV valve took quite a bit of coaxing.

Urambo Tauro > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:30

Call me old-fashioned, but I like copper-core plugs. It’s a great conductor, and the accelerated wear (compared to platinum or whatever) gives you an excuse to turn a wrench every once in a while to help keep the plugs from getting badly stuck. They’re usually good for about 30,000 miles.

facw > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:35

I used these NGK ones last time I did mine: https://www.amazon.com/gp/product/B000BYDA8E

I don’t really have much to say about them? Seemed like pretty normal precious metal plugs.

beardsbynelly - Rikerbeard > Urambo Tauro
04/17/2018 at 17:36

I run copper cores, but I’m also running higher boost and a somewhat leaner tune. I don’t see the point on an unmodified engine though.

Steve in Manhattan > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:46

This is a relatively cheap bit of preventive maintenance, and if it makes you more comfortable, then why not?

dogisbadob > Full of the sound of the Gran Fury, signifying nothing.
04/17/2018 at 17:52

Iridium spark plugs are usually good to at least 100k

The best ones to get are the Denso Iridium TT

But the Denso Iridium Long Life and the NGK Laser Iridium are both good choices as well, and the OE plugs will be either of those two.

diplodicus forgot his password > beardsbynelly - Rikerbeard
04/17/2018 at 18:01

Coppers cheaper than platinum and iridium.

crowmolly > Urambo Tauro
04/17/2018 at 18:06

Kind of depends on how easy they are to change. Some cars have you rocking engines, pulling motor mounts, removing intake manifolds, etc to get at plugs. Not worth it then.

beardsbynelly - Rikerbeard > diplodicus forgot his password
04/18/2018 at 04:46

not in practice from my experience.
I can get NGK laser iridiums for about 3x the cost of the NGK coppers, and I’d get more than 5x the life out of the Iridiums.

pip bip - choose Corrour > Full of the sound of the Gran Fury, signifying nothing.
04/18/2018 at 06:43

NGK