Is it critical to replace plugs at manufactureers specified milage or is there some leaway here? looking for experiences from owners of the 8 to give me some insite.............cheers munroco

 

There is leeway....in both directions. Plugs can fail VERY quickly, or they can last a LONG time. Considering the problems that failing plugs can give you however, every 30k is a good rule of thumb.

Make sure to do your coils and plug wires at the same time though. One failing can accelerate the failure of others, or outright kill them. Even if the others are new.

 

Depends on a lot of factors...

older plugs will give weaker sparks over time. weaker sparks lead to more unburnt fuel being dumped into the CAT (reduced performance too). unburnt fuel in CAT leads to increased wear on CAT. Premature CAT failure leads to anger. Anger leads to hate. Hate leads to suffering..... then your journey to the dark side will be complete.

 

I change mine once a year regardless of miles to be safe. I have owned my 8 many years and it's just based on what I see. For me it's peace of mind.

 

IF cost is what your holdup is, I doubt you are going the cheapest method. Plugs are $80 USD. Anything more is overpaying. Dealers will charge you $160+, plus another hundred or few for labor. 10 minutes or less to swap them out yourself.

 

10 minutes? Damn your fast

 

Plugs in rotaries tend to degrade easily and in weird ways. Oddly, sometimes you can take a look at plugs and think they look pretty good, but an engine won't even start with them (this seems to happen to the plugs on on fresh untunned/horribly flooded engines). Other plugs can have significant issues and the car will run. I once found the plugs in my RX-7 were in horrible shape. One trailing plug was missing 1/8" of the electrode and the car ran pretty reasonably (albeit a tad rough).

Bottom line: Deliberately not changing spark plugs to save money is not worth it.

 

It's about what it took me. Didn't need any craziness or anything. 3 socket extensions and I didn't even need to remove the wheel or angle my arms to anything. The socket extensions gave enough flex in the angle that I could just turn the wheel to the right, pop a plug wire off by hand, pop the plug socket over the plug, pull out, put the new in, refasten the wire, move to the next. Seriously took me like 10 minutes.

 

Well I have done it many times on my 8 and quite a few on others and it still takes me a bit but then again I am never in a rush and I am always running my mouth which definitely slows things down,

 

Thanx everyone; I'll get right on it. The info re: plug cost Is helpful. I got a quote of over 200.00 for the plugs alone. better shop around. And get out my floor jack for the change over. what should a good set of wires cost and what pitfalls, if any, are present. cheers M

 

$200 for spark plugs?!
Should only cost you $80:
http://blackhaloracing.com/products-...-heat-ranges4/

You can get them at other places... I usually drive up to Summit Racing.

 

Go to www.raceroots.com

4 plugs, 4 coils, 4 wires $342 CAD all inclusive at your door.

 

Anyone know where is a good place to get my plugs replaced if I have the parts? Last resort will be dealer but that will surely burn a hole in my wallet

 

I placed an order with RaceRoots last week. I've been quoted $300+ CAD by dealerships in Toronto for just spark plug replacement. They sell plugs at $60 each. RaceRoots has plugs + wires for $130 (~$150 CAD w/ shipping). Even if I get someone to install them at shop rate, I'd still save. But I'll be doing it myself.

 

Yes, buy from Raceroots, and its something you can do yourself.

 

Don't forget the spark plug grease. I get mine from partsource.

And if you can get or borrow a torque wrench, much better.

 

I was planning on buying from there but I'm not very confident that I'll be able to do it myself. Spark plugs seem ok but the coils seem very hard to reach. Just wondering if anyone has brought it to a mechanic to swap out the old ones

Thanks!

 

Coils are easy to replace with some help of socket extension. No need to remove the air filter housing (if you want to work tight..lol..)

Don't over torque the nuts. They are too soft..treat them like an egg..lol..

I broke mine last time so i have to take out the plate where the coils are sitting in..

 

I was just quoted ~$350+GST to get the plugs replaced at the dealer, including labour...

 

plugs and labor only?OMG...I pay $342cad for my plugs,wires n coils shipped to my door..and as I remember $11 for tax...

I ordered mine here

http://raceroots.com/index.php/produ...on-bundle.html

Replace it yourself..its easy...

 

What's more important when it comes to replacing plugs & coils - miles or age?

I have a 5yr old rx8 (first owner) with low mileage (24k). For about 3 years I only drove it 2-3 times a month. Going forward, I'll be driving more frequently - but probably no more than 200-300 miles a month. The car has been in great condition (live in NJ/NY area and have had no problems with cold starts or rough idle). Have been doing regular oil changes every 2-3k miles but that's it.

Don't mind spending the $ on the maintenance - but also don't want to bring the car to the dealer if I don't have to. Have been considering bringing it to the NJ dealer while I'm home for the holidays to do this plus MT / diff oil replacement - but am looking to you guys for guidance. What do you think? I know the car is 60 months old - but it's also well under 30k miles and drives fine.

Thanks

 

It's more of a mileage...or use issue than time.

If you drive the car hard the plugs will wear out....if you baby it..they will carbon up like the rest of the system

At 30K you likely should be looking for new plugs soon...and coils too if you get any driveability issues

 

i have ordred plugs and oil filter from race roots. still waiting for them.

 

Search is your friend. Behold the DIY for how to change your coils and plugs. At most 1 hours work with simple hand tools and a floor jack.

https://www.rx8club.com/series-i-do-yourself-forum-73/diy-mazda-ignition-coils-pics-178515/

 

Ok quick question about this...... I have seen plenty of stuff on when/why to replace the plugs and coils, but haven't seen much about when to replace wires. Do the wires require replacing at a similar time too, or do most people just decide to switch them out with the plugs and the coils while they are at it?