New RX-8 COILS every-time you Replace your PLUGS?
 

I am just putting this out there for more experienced members than I on the subject of RX-8 Ignition Coils.

As we know the Coils are not going the distance and Mazda have updated materials used, BUT, it appears they can and will expire also.

So should we be replacing coils at the same time we do our spark plugs?

Here is another reason WHY, this was put to me by a UK based Rotary Owner and forum owner.

At the early stages I had heard that many dealers all over the world were replacing engines that were OK but they would not start, in reality it was just that the Ignition was stuffed, Coils, Leads, and maybe plugs, but particularly the Coils.

He said this...""the older the coils get the less charge and spark they are putting out, this then results in a poor spark and then a lot of Fuel Wash, or unburnt fuel, which then dilutes metered oil for Apex Seal lubrication and oil viscosity in general then creates yet another set of problems in regard to engine and seal wear, poor fuel economy and performance""...

So what do you guys think....RG, MM, Swoope

Should we be be replacing all Ignition parts (coils,leads,plugs) sooner rather than later??

I made it a habit to replace the coils and plugs once a year just to be safe. (and because I'm a bit obsessed with preventative maintenance)

do we HAVE to change them every time? probably not.... would I suggest it? Yup.
Lots of factors here though as Heat can be a major factor in the life of OEM coils so some might get away with running oem coils for 30-50,000 miles and others might need to do it more frequently.

Every Year!!, How many miles do you do in a year?

every 2 years or 25,000 miles i change mine...

Well, for plugs, I change mine every 10-15 K miles.

but for coils, change it only if its showing problems, for example, Misfiring happen @ high rpm, plugs changed still same thing.

I got a set of BHR coils at 25K miles and I hope not to be changing coils until my motor goes out and i need to return my motor to stock. Plugs were slightly carboned, but still pretty healthy at that point. I replaced my leading plugs because I had a spare set in my glove box. Your plugs may vary depending on how the car has been taken care of.

Change or check your plugs every 20K, they are cheap and easy to do yourself. For the coils, you could wait till you start getting misfires, or change them at some pre determined point between 25K and 35K miles. Coils seem to fail slowly over time instead of suddenly. It would also be wise to change the plug wires at the same time as the coils. Wires go bad over time too.

I have over 50K on my stock coils. I plan on replacing them, but think I will go the BHR route instead. Hopefully than it wont be an issue with having to replace them so often.

what id like to know, can we rotate the coils to try to get the maximum amount of life out of them. Like switch the 1st coil and 2nd coil....then switch the 3rd and forth around...that way they get the same amount of usage? i figure this would be a good mid point adjustment to get some more life out of the coils since the 1st and 2nd set work differently.

I planned on doing this when i do my plugs again soon, just a thought.

so.. which of your coils is doing less work then the other 3? or do you mean you want to move a "going bad" coil around so it can maximize it's coverage across the engine?

if you're looking to increase the usage then go the "replace as needed route". You'll have to test your coils on some regular basis and simply replace the one (or two) that are falling outside of spec.

personally i dont trust the stock coils on these cars.

i'd do a personal upgrade, wouldnt buy a kit but thats just how i am. I'd build it myself to be sure everything is to my personal choice. Aftermarket coils are nice, plus rotaries run rich so a "stronger spark" is always better IMHO.

kevin.

Kevin, I'm all ears ..... can you provide any details on the kit you'd build? Which aftermarket coils would you recommend?

Have we come up with a reliable test? If so, where is it or what do I search for?

Never fear, Jedi is here

http://www.finishlineperformance.com...16-07-1793.pdf

Hi Kevin!

Agree on the strong spark, is there any truth to the fact that a poor spark will result in a lot of unburnt gas (liquid) resulting in fuel wash and degradation of metered engine oil for Apex Seal lubrication, etc..

In other words what my UK friend says (see my first post) is correct.??

According to those in Cold Climates the white marks or burn marks do not always show, so you can have poor or bad coils without any tell tail visual signs...

Ash

I thought I read that it was expected that unburnt fuel that would sweep into the next combustion cycle. I'm thinking it could possibly be more the alcohol that is added to the fuel that is diluting the oil.
It sound like a reasonable plan to change coils with the plugs. The problem being that on top of spending $80 (U.S.) for plugs, now we will be adding $120 (minimum) to that for the expense of the coils also. Getting the owners to do that would be difficult.

That's the idea! I'd rather change a part once and never have to deal with it again. Plus, with the increase in power output with the BHR coils the car overall feels much better to drive.

Kevin, I can relate to your DIY attitude. I'm not trying to sway you away from building your own kit. I can tell you there are at least a couple individuals here on RX8 club that have done the very same thing and in the end commented it would have been easier to buy the upgrade. In the case of BHR, we've done all the heavy lifting and design for you.

Jedi, Thanks. IIRC, people were not getting consistent results with C - IGNITION COIL INSPECTION (coil ohm meter test). I just tested 4 new coils, and got the expected results.

Had tested them previously with different meters and did not get the expected results :confused:.

Anyone looking for plugs, Amazon.com dropped their price for the NGK OEM plugs to $66 shipped :icon_tup: .

The TSB says "DO NOT diagnose ignition coil condition based on “white spots” or “heat marks” which may be found on the bottom of the ignition coil body."

ASH8, Are these "white marks" and "burn marks" you speak of different than the “white spots” or “heat marks” that the TSB is saying to ignore?

The primary issue from Mazda's standpoint is their tolerance levels have a HUGE range. I don't know the specifics off my head but I can say that Mazda considers coils to be "acceptable" in operational ranges which are less than acceptable in the RX8.

That being said, any kinds of values you find from Mazda may not actually be where you need them to be.

I have an idea - lets start another coil thread!
We can all talk about white spots and coil failure indicators.
Again.
For the ninetieth time.

White spots = no useful diagnostic value
TSB Coil Test = marginal value
Test under load with a timing light = only worthwhile test

I've been on the BHR coil system for 1.3 years. That is 3 sets of OE coils in my world.

The *TOPIC* of this thread I started was asking the question "Should Coils be replaced at the same time when you do your Plugs"

Good for you you have been on the BHR system for 1.3 years, great it works well.

Some of us may not wish to or be in the position to change to BHR...a product you promote.

Some may want to stay with OEM Coils.

BTW: MM, any news on Access Ports for 09 8's?

Is there a link to the BHR Coil System with Pics, had a quick search, apart from going through 15 thread pages...thanks..

My point was simply that you probably should replace OE coils at every plug interval - or even more often.
Or, you can use something else and not have to do that anymore.


Nope. As soon as I know something, you will know something.