Notices
Series I Trouble Shooting This is the place to learn more about or discuss any issues you're having with your RX-8

What is reasonable plug life?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 03-01-2011, 09:11 PM
  #1  
second car is a broom
Thread Starter
 
Hespra's Avatar
 
Join Date: Sep 2004
Location: Portland, OR
Posts: 70
Likes: 0
Received 0 Likes on 0 Posts
What is reasonable plug life?

Can't find a thread on this issue. Sorry if one exists and I missed it.

Question:

How often--in terms of months/years or mileage-- would you expect plugs to perform well? I'm now on third set. Odometer at 35,000.

Thanks for your help.
Old 03-01-2011, 09:33 PM
  #2  
Registered
 
Old Rotor's Avatar
 
Join Date: Jul 2004
Location: Northern California
Posts: 2,196
Likes: 0
Received 0 Likes on 0 Posts
If you are stock 35K, but we have seen them go much further on a good tune and all hi-way. The problem is you don't want to take a chance and have one fall apart into an engine....If it gets flooded you might need to change them earlier.
Old 03-02-2011, 12:07 AM
  #3  
I HATE SPEEDBUMPS!
 
monchie's Avatar
 
Join Date: Nov 2007
Location: Las Vegas, NV
Posts: 8,549
Likes: 0
Received 7 Likes on 6 Posts
Well, standard copper plugs are said to last anywhere from 10,000 to 20,000 miles (16,093 to 32,187 kilometers), while more expensive iridium or platinum spark plugs can last 60,000 miles (96,561 kilometers) or more. Some high-end iridium plugs are advertised to go more than 120,000 miles (193,121 kilometers), but there's no actual guarantee they'll be able to achieve this.
Old 03-02-2011, 12:21 AM
  #4  
Dragon Certified
iTrader: (1)
 
987HYS's Avatar
 
Join Date: Dec 2005
Location: Roanoke Tx
Posts: 829
Likes: 0
Received 0 Likes on 0 Posts
My OEM ones lasted 72k. my service advisor was shocked and told me they were supposed to be changed every 30k
Old 03-02-2011, 12:22 AM
  #5  
Registered
 
Old Rotor's Avatar
 
Join Date: Jul 2004
Location: Northern California
Posts: 2,196
Likes: 0
Received 0 Likes on 0 Posts
Stick with the OEM NGK plugs.
Old 03-02-2011, 12:44 AM
  #6  
is adjusting valve lash
 
TrochoidMagic's Avatar
 
Join Date: Sep 2007
Location: hollywooood!
Posts: 1,060
Likes: 0
Received 0 Likes on 0 Posts
on this car... i'm fine with not leaving anything to chance and change at the recommended interval, or sooner.

the originals that came with the 8, was replaced at 25k when i inspected it due to intermittent misfire. sure enough,the insulator on one had a hair line split by the electrode...

imagine if i didn't catch that, and the ceramic insulator dislodged into the housing, with just less than 25k on the car. i'd be one pissed off 8 owner, and a member of the new engine club, on a new car!
Old 03-02-2011, 06:03 AM
  #7  
Registered User
 
mycroft's Avatar
 
Join Date: Feb 2011
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
These were my stock plugs after 35,000 miles.

Name:  qoDlo.jpg
Views: 10
Size:  68.8 KB

At 25-30k I'd start pulling them to check their condition.
Old 03-02-2011, 06:31 AM
  #8  
#50
 
bse50's Avatar
 
Join Date: Nov 2007
Location: Caput Mundi
Posts: 7,521
Received 10 Likes on 10 Posts
20.000 miles of normal use with properly working coils. They're a cheap maintenance item so there's no need to be stingy!
Old 03-02-2011, 06:38 PM
  #9  
Registered
 
Old Rotor's Avatar
 
Join Date: Jul 2004
Location: Northern California
Posts: 2,196
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by mycroft
These were my stock plugs after 35,000 miles.



At 25-30k I'd start pulling them to check their condition.
I don't believe your left plug was firring....... did you replace the coil or wire?

Last edited by Old Rotor; 03-02-2011 at 06:47 PM.
Old 03-03-2011, 12:00 AM
  #10  
I HATE SPEEDBUMPS!
 
monchie's Avatar
 
Join Date: Nov 2007
Location: Las Vegas, NV
Posts: 8,549
Likes: 0
Received 7 Likes on 6 Posts
That looks bad...
Old 03-03-2011, 01:48 AM
  #11  
I drive at Red Line.
iTrader: (1)
 
DocBeech's Avatar
 
Join Date: Jul 2010
Location: Dallas, TX
Posts: 2,137
Likes: 0
Received 5 Likes on 5 Posts
Im at 67K on OEM Plugs and Coils.
Old 03-03-2011, 06:46 AM
  #12  
Registered User
 
mycroft's Avatar
 
Join Date: Feb 2011
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Old Rotor
I don't believe your left plug was firring....... did you replace the coil or wire?
No. I had a CEL for a misfire and replaced the plugs. It went away. Everything runs fine now and I've checked the plugs (5k miles later) and they look normal.

FWIW the other rotor's plugs looked pretty much the same.
Old 03-03-2011, 07:57 AM
  #13  
It's Complicated
iTrader: (2)
 
Pico's Avatar
 
Join Date: Feb 2008
Location: Dirty Jerz
Posts: 1,780
Likes: 0
Received 0 Likes on 0 Posts
Your on par with me

I change mine every 15K and coils every 30K even if there still in good shape, cuz I'm crazy like that.

Mazda say's to change plugs every 30K, but we all know that the life of mechanical parts can very from car to car.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Jesus Martinez
Series I Aftermarket Performance Modifications
72
07-26-2023 11:29 PM
badinfluence
Series II Aftermarket Performance Modifications
6
08-31-2015 11:51 AM
dancingdan42
RX-8's For Sale/Wanted
0
08-19-2015 09:29 AM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: What is reasonable plug life?



All times are GMT -5. The time now is 12:40 PM.