TorqueMonster

I didn't realize how much more expensive S2 coils cost! The dealership wants $80 each for S2 coils! Where is everyone buying S2 coils and for how much?

paimon.soror

iTrader: (15)

Advance Auto Parts

There are a ton of coupon codes floating around. I recently used "TRT41" for $40 off $100

Grace_Excel

iTrader: (5)

I'll post this from alnielson's reponse to yours, paimon, from another thread.

ASH8

You can buy on-line for $62.62 each from a Dealer ...

Mazda Parts - Online Mazda Parts

BTW: According to another member even though the Part Number (B9U in USA) is saying B9U the Coils inside the box are the very latest 'C' iteration (as used in the 2012 RX-8 Spirit R Japan)...look on side of the Coil to see a C (small) stamped on it's side, I can not confirm the members statement of fact, but I have no reason not to believe it.

BTW: These Coils are for all Series RX-8 not just S2's.

paimon.soror

iTrader: (15)

Like I said ... you can get coils from AAP for 80 total using a coupon code and they come with lifetime warranty. I along with many people here use them without issue. Paying 60/80 bucks for each coil is senseless unless you are made of money and the mazda box makes you feel warm and fuzzy inside.

ASH8

Yeah ,we heard you M8....

BTW: are AAP Coils B's or C's?

paimon.soror

iTrader: (15)

Couldn't tell you. B rev at the very least. Albeit one could compare them to C rev due to the recessed base. But I have no reason to believe C rev is any different / better without qualitative data.

ASH8

Each Coil iteration from plain OE part number (no letter) to A to B to now C has seen an 'improvement' in reliability with Mazda dictating they are a one way only super-session which means 'improvements' have taken place.

Whenever they change, modify or improve any OE parts while car is in production apart from VIN details they always assign a interchange code to assist Mazda Parts Dealers in the correct supply of parts plus any additional parts if required to use with new updated part, the 5 assigned codes used from 1979~ are listed below....
If any OE part has undergone a change in manufacture supply then details of the maker is also shown, if part has not change manufacture then no brand logo details are listed.

From Mazda...

Mazda Parts interchangeability code and meanings... (A, AN, C, G or S).

paimon.soror

iTrader: (15)

considering no RX8 other than the SR came from the factory with C coils, i dont think that is an issue here .


And as an engineer, I should advise you not to believe everything the marketing department tells you. There is absolutely nothing that would prevent the usage of an A rev on an engine that came with a C rev coil.

Lastly ... I would be intrigued to see proof of a C rev's increased reliability compared to B rev. Considering C rev is fairly new ... we have about 5 years before we have significant usage/data to make an accurate assumption.

ASH8

This is not from a "marketing department"...this is from an engineering department within Mazda Japan and has been their parts identification and install practice for replacement OE Parts for many decades.

The 'C' Coil revision came out in September 5 of 2011 production...as an A interchangeability coded part.

I will definitely call the C's a better version, so far the B's have outlasted the A's and the A's outlasted the originals, so I have no doubt that 'generally' the C's are the better OE Coil.

IF the 'C' Coil was not an improvement then Mazda engineering would have listed the revision coded as one of those below.

The other 4 of the 5 Mazda Parts interchangeability codes and meanings (AN, C, G or S) which are not related to latest OEM 2012MY 'C' Coil...

Or

Or

Or

Edit: Changes to the 2012 Spirit R RX-8 'under hood' was only to the 4 Ignition Coils ('C' # iteration), these are now the only Coil Mazda issues to all Mazda Distributors worldwide for use on all series RX-8's from 2004 on-wards.
No other changes under the hood, same as 2011MY.

Are you an automotive engineer Paimon?

paimon.soror

iTrader: (15)

lol ... smh ....

Automotive engineer? No, But I am in fact an engineer with a degree in computer, and electrical engineering ... and I work for an aerospace engineering company.

you would be surprised how the real world of engineering works.

Anyway ... OP should have enough information to make a decision




edit: BTW, automotive engineers aren't the ones making ignition coils .... for future reference. Therefore, I guess you could reword your query to "Are you an electrical engineer" ... then I would say "why yes, yes i am"

ASH8

Wow...

fyrstormer

Paimon, I think Ash did a pretty good job of explaining why the new part can be reasonably considered an improvement. The ignition coil assembly is a black box as far as everyone except its designer is concerned; if it were functionally identical at all interface points, then regardless of its internal components, it would've been labeled as a 1:1 substitute, instead of being labeled as a part that can't be replaced with an older version. And I say this as an engineer with qualifications comparable to yours.

It sounds like maybe you've intentionally misled customers in a professional capacity before, and you're trying to make yourself feel better by assuming everyone does it. We don't.

paimon.soror

iTrader: (15)

Edit:

Removed original post. At this point I am not going to argue. Buy C rev.

paimon.soror

iTrader: (15)

Btw, I will wholeheartedly apologize for clearly offending both you and ash if either of you can go out and find out exactly what prevents someone from installing a B rev coil onto a car that came with a C rev coil.

And please dont quote any Mazda Corporate documentation ... get me some nice hard factual evidence ...

I'll be waiting.

Until then ... run along and await the spoon that feeds you

Charles R. Hill

iTrader: (7)

There is one other possibility as to WHY Mazda issued these alleged "revisions" of their ignition coils, and why ASH8 may have some particular (though likely coincidental) knowledge/experience on the matter; global compatibility.

Personally, I have no idea what (if any) improvements may or may not have been made throughout the years with Mazda's OEM ignition coils. On the other hand, I can (from direct and personal experience) tell you that the varying regions of the world have different PCMs and not all PCMs will work with the same ignition coil.

ASH8, is it possible these OEM coil revisions have simply been so Mazda can use the same ignition coil on all RX-8s worldwide?

fyrstormer

Possibly, but since the PCM isn't going to be replaced, there would be no reason why a car requiring replacement ignition coils couldn't use a new globally-compatible ignition coil *or* the original region-specific ignition coil. So there would be no reason to label the newer, globally-compatible ignition coil as requiring replacement with the same or newer part, when the older region-specific part would still work fine with the car's PCM.

ASH8

Charles R. Hill (Mazda does 'revisions' to many OEM parts) the Coils Mazda use are the same for all world regions, production install updates are done for all countries @ about the same time....the RX-8 comes off the same production line, the updates happen when they make the cars for 'a' particular region...obviously.

The latest OEM 'C' Coil fits all RX-8's of every series of every RENESIS engine worldwide...as did the plain, A and B of their time...but they are one way replacement install only.

Mazda USA, Mazda Australia/NZ, Mazda Europe and Mazda Japan EPC confirms exactly this.

Really...yes...PCM's are different for different regions, however the Coils are not, provided the latest supplied Coil is used....more than likely what has occurred 'if' a CEL or issue may have happen is the installer or owner or 'expert' has specifically gone against what Mazda says...their parts interchangeability codes I issued are there for a reason....in other words install an old supply new Coil in a model which requires the originally installed newer updated later Coil = problems.

All OEM RX-8 Ignition Coils are new iteration replacement for old, not old supply part install for car which has or had a later part (newer).

If someone buys a 'OE' Coil off a supplier say on eBay and it is an 'old' iteration designed for a RX-8 of say a 2005 MY, and installs it on a 2007 MY RX-8 then YES, they may have issues...(new for old, not old parts supplies for new as Mazda specifically advises).

Separately like many other Mazda parts the PCM's has the same cautions, there are literally 10's of updated RX-8 PCM's for all world regions for separate use, and in 9 cases out of 10 they also are only new for old supply replacements whenever renewing a PCM/ECU...

IF you try and mix them up (PCM) with older Coils also you are asking for problems....let alone 'as built' calibrations with a changed/wrong OE PCM (good luck there too).

All of the RX-8 OE Coils Mazda has supplied to them looks physically identical, the only way to identify what iteration they have in their hand is to look at the part number reference ''single alpha letter'' stamped on coil side...(plain (no letter), or A, or B, or latest C), or the meaning 'plain' up to 03/2006; or 'A' up to 12/2007; or 'B' up to 09/2011; or 'C' from 09/2011 production, respectively.

Put very simply, IF an owner (wants to) uses the very latest issued OEM Ignition Coils set (available from a Mazda Dealer) you won't have any compatibility issues with OE PCM (as allegedly reported by some with older made OE coils, but with no proof) or anything else with any RX-8 ignition world-wide.

Edit: One would think every other Mazda parts update done to their cars since they have gone from making 3 wheeled bikes/truck in 1949 is also a 'marketing exercise', I guess the exact revisions to a well know other RX-8 part (try Coolant Bottle) is also not to address a 'technical issue' but a 'marketing campaign'.

RIWWP

iTrader: (2)

Ash, from an electrical perspective, I can't see a single reason why the following sequence would be true:

- Original coils on engine
- Revision A coils on engine
- Revision B coils on engine
- Revision A coils on engine
(or any other 'step back')
- problems occur due to the step back

The only way that there could be a problem stepping back is if
A) there is some sort of learned parameter within the ECU that recognizes the coil revision, and stores it.

AND B) there would have to be subsequent flashes of the ECU for the ECU to understand that it needs to do something different with a C coil than it does with a B, A, or original coil. (and that addition coils even exist!)

AND C) this learned parameter can not be "lost" during a battery disconnect or 20-brake-pedal-stomp reset

An an illustration, If a 2004 RX-8 last had it's ECU looked at or connected to a dealer's computer for MSP-16 in 2005, how could it know about C coils at all? The C coils didn't exist as of the last time the ECU's concept of the world and parts possibility was updated.


The string of requirements for a step back to cause a problem for at least a series 1 RX-8 is significant, and I have not once seen anything that would support even one of those requirements.

Am I wrong?