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

J, K, L, and M Flash Explanations

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 07-25-2004 | 11:02 PM
  #1  
PoLaK's Avatar
Thread Starter
Son what is your Alibi?
iTrader: (1)
 
Joined: Sep 2002
Posts: 2,205
Likes: 2
From: Washington, DC
J, K, L, and M Flash Explanation

Yes i know another thread on Flashes, but seeing as the sticky is getting a bit long and all the info isn't localized in to one informative post i figured that i would copy the article I wrote on the JKLM flashes for the May issue of Rxtuner (www.rxtuner.com) If you haven't subscribed yet, do it, lots of good stuff in there, this month (July) i did extensive testing on the Canzoomer Stage 1 unit and offer a informative logical explanation as to why it doesn't work with a decent percentage of cars that have it equipped.



J-K-L-M do you know your re-flashes?
Mark Gaal “PoLaK”



Where is the Power?

Rx-8 owners across the country have gawked at the low dyno numbers the Rx-8 is producing. The 8 supposedly makes 238hp at the crank which should translate to about 190-200whp taking into account drivetrain and frictional losses. Actual mustang and dynojet numbers are much less, ranging from 168-180whp (wheel hp). So, where did the power go? Well popular belief is Mazda screwed up, back in May/June of last year when pre-order buyers were expecting their cars, there was a long hold up at port. The cause behind it EPA2 emissions regulations, Mazda had forgotten that the Rx-8 would have to meet newer and more rigid requirements for the 2004 model year, specifically a Catalytic Converter that would have to last 170k miles. So to satisfy the already anxious and complaining pre-order buyers Mazda flashes all the cars waiting at port with a J. It’s signified by a “JX” port campaign sticker under the hoods of the first shipment of Rx-8’s to the US.



Problems with J

J is pretty much Mazda’s half-*** attempt to meet EPA2 and get buyers their already deleyed cars. The entire J flash is rich meaning, to preserve Cat-life, Mazda used a fuel map that tuned the Air to Fuel Ratio (AFR) pig-rich across the powerband. What this effectively does is pack more fuel in to the combustion chambers then there is air to combust it. This un-burnt fuel then keeps the exhaust temps down, thereby preserving Cat-life. Everything is spiffy for the first few weeks, until a couple of the more enthusiast oriented owners go out and dyno their then 247hp cars. They find the low dyno numbers, post it on sites like Rx8club.com where it is debated. Soon after Mazda issues a revised Horsepower number 238 (which is still a bit optimistic). They offer owners or pre-buyers that bought before this announcement a $500 debit card and free maintenance for the life of the warranty or a buyback of the car at purchase price. Not a bad deal for 9hp, but the reason behind it isn’t a “calculation” error.



K

K came along after Mazda had a few months to research into what would be the best performance/mileage VS Cat-life flash for the RX-8. K from an engineering standpoint was light-years ahead of J. Mazda leaned out the AFR though some of the powerband, although Mazda was still playing it safe from around 6800rpm to redline where the flash became rich. Again, this had to be done due to the natural high-heat out-put of rotarys. However to Mazda’s surprise they began receiving reports of Cats failing, not because of high-heat, instead the un-burnt fuel from running so rich, began accumulating in the cat effectively corroding it. So the engineers at Mazda come up with an idea that is, well a first in the sub $100,000 car market, a little jewel called “L”




L

The L Flash was a major recode of the ECU. Obviously Mazda has been putting some serious hours into R&D. Most of the complaints have been centered upon less than smooth around town driving, and poor gas mileage. Fixing these issues is harder than it seems, numerous factors have to be considered. The Air/Fuel mixture has to be lean enough to get good mileage, but rich enough to prevent pinging. It also has to be smooth for general driveability, and still produce the expected power. Juggling all of these issues can be very challenging. Mazda’s answer is essentially to pack two maps into one ecu. The L Flash gives one map for gears 1 through 3, and one for gears 4 through 6. Reasoning being, that load, and potential for pinging, are higher in gears 4 through 6 because loads on the engine are higher as speeds increase. So with the previous flashes, the tuning may be right for highway driving, but very rich for the lower gears. So the big difference with “L” is it tunes based on what gear you’re in! Active tuning is accomplished by voltage readings provided by the MAF sensor as well as another variable sensor. It leans or richens the fuel mixture at different points based on gear. For example in 3rd gear the AFR is pretty lean up until about 4,600rpm where it becomes very rich, very fast. Now in 4th gear the AFR is pretty lean until 2,900rpm then it becomes much to rich. Although “L” is a major improvement, these dyno results show that there is still room for improvement. Hats off to Mazda for releasing a product that delivers significant improvements.



M

The M Flash is a further evolution of L, trying to improve more on mid-range smoothness, gas mileage, and cold start flooding problems. It seems as though Mazda released the RX-8 with maps that they knew were too rich, and incrementally are re-flashing the car until they find the sweet spot. This isn’t too bad of an idea for reliability, unfortunately there are side-effects, or else there would be no need for all these flashes. “M” further leans out the mixture in the low and mid-range rpm areas for all gears. This will give a bit more power, smoothness, and mileage at those points. Another change in the M flash is that when cranking a cold engine now, the first 3 seconds there is no fuel injected. This was done to combat the complaints of flooding in cold engines. Early reports of those on www.rx8club.com who have received the M flash substantiate these claims. Almost all have reported noticeable results, especially in the feeling of more mid-range punch and better mileage. It’s to early however to know if the flooding problems are resolved, but you can’t argue that Mazda is trying. It’s a very exciting change from how things were done in the past, where if you wanted a better driving car, you only option was to wait for the next model year. Now all it takes is the ingenuity of some Mazda engineers, and 30 minutes at your dealer.
Old 01-15-2005 | 12:11 PM
  #2  
Omicron's Avatar
Registered
 
Joined: Oct 2001
Posts: 7,966
Likes: 4
From: Boulder County, Colorado
For questions and discussion on flashes, see this thread.
Old 01-31-2005 | 04:09 PM
  #3  
jayrob33's Avatar
Registered User
 
Joined: Sep 2004
Posts: 27
Likes: 0
L OR M FLASH, WHAT IS THE DIFFERENCE? what is better?

hello all,

i have been reading on the forums here about this "M" flash change to the PCM. i just called my dealership today and they said that they can change it for me at any time. i was never contacted by mail for this recall, must you have a letter or proof when u take it in to get fixed?

also, will this M flash help my car start better in cold temps. i have never flooded the engine, but from time to time, the car will have some trouble starting after sitting in the cold for a while. is this recall like an upgrade for the car to stop it from doing that?? how will i know what flash that i am getting. i have also read about an "L" flash. is that what my car currently has?? is the "M" better?


pls help with any feedback.
Old 01-31-2005 | 04:25 PM
  #4  
zoom44's Avatar
Administrator
 
Joined: Jul 2002
Posts: 21,958
Likes: 115
From: portland oregon
it is NOT a RECALL. dont worry about not having a letter. if you are on L then yes you should get a newer flash IMO. however there is no M now as we have finally moved on to the N flash. we have no way of knowing what flash you actually have. but we can guess with some info-

what is your cars build date
when did you buy it
have you been in for service before.
if so, do your service papers say anything about a pcm upgrade?
Old 01-31-2005 | 04:39 PM
  #5  
jayrob33's Avatar
Registered User
 
Joined: Sep 2004
Posts: 27
Likes: 0
my rx8

built 9/03
bought in 4/04
i have not been in for service before, but have noticed over the last couple months that i have been having trouble starting in cold weather.

if i contact my dealer, will they now which flash they currently have? should i ask for the N? what is the benefit of the N flash?
Old 01-31-2005 | 06:39 PM
  #6  
zoom44's Avatar
Administrator
 
Joined: Jul 2002
Posts: 21,958
Likes: 115
From: portland oregon
they use a machine called aWDS to diagnose and help repair things. when they hook up the WDS they will see what level you are on and then they will check to see if there is something newer. the WDS will tell them there is a newer one than what you have availble and they will flash your pcm with it. it contains everything up until it plus what ever changes were made for it. there is no need to load any inbetween flashes. if the dealer did their job and made sure your car was up to date when you bought it then you already have M. if they didnt then you are probably are on L and you will notice a difference in the power band when they flash your car to N
Old 02-15-2005 | 07:06 PM
  #7  
Sponge Bob's Avatar
Registered User
 
Joined: Feb 2005
Posts: 63
Likes: 0
From: Northern California (East Bay)
Wink Got "flashed" today

Got my new '04 updated to the latest version of flash (N). Unfortunately, I can't really make a comparison to the original version (L, I believe) as I've only had the car since Saturday and only put 175 miles on it in that time.

I stopped by a local independent rotary performance shop (Rick's Rotary Performance, Pleasanton, CA). My understanding from my conversation with Rick is that L provided a quantum leap (in performance and fuel economy) over J and K, and that M and N largely provide refinements to help reduce flooding. His '04 came with K and he noticed a big difference when he upgraded to L (which reamins is his current version).

Per recommendation from pbuck1 and Rick, I will will likely change the tranny and diff fluids to Redline at the initial oil change.

I have ordered a dashmat and clear corners. Found the clear corners on eBay for $55. (link: http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WDVW). Seemed like a better deal than I could find anywhere else on-line.

I'll post pictures of my new "baby" once it stops raining and I can get a good shot. It's supposed to rain all week. Oh well, this means more snow in the mountains and better fly fishing in the summer and fall.

Later,
Bob
Old 02-16-2005 | 12:33 AM
  #8  
G8rboy's Avatar
Mmmmm... Rotary Donut
 
Joined: Nov 2003
Posts: 2,376
Likes: 4
From: Lake in the Hills, IL (NW Chicago Burbs)
Originally Posted by Sponge Bob
Got my new '04 updated to the latest version of flash (N). Unfortunately, I can't really make a comparison to the original version (L, I believe) as I've only had the car since Saturday and only put 175 miles on it in that time.

I stopped by a local independent rotary performance shop (Rick's Rotary Performance, Pleasanton, CA). My understanding from my conversation with Rick is that L provided a quantum leap (in performance and fuel economy) over J and K, and that M and N largely provide refinements to help reduce flooding. His '04 came with K and he noticed a big difference when he upgraded to L (which reamins is his current version).

Per recommendation from pbuck1 and Rick, I will will likely change the tranny and diff fluids to Redline at the initial oil change.

I have ordered a dashmat and clear corners. Found the clear corners on eBay for $55. (link: http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WDVW). Seemed like a better deal than I could find anywhere else on-line.

I'll post pictures of my new "baby" once it stops raining and I can get a good shot. It's supposed to rain all week. Oh well, this means more snow in the mountains and better fly fishing in the summer and fall.

Later,
Bob

Good advice on the tranny/diff change with Redline... you'll notice the difference in the gearbox... and you get the break-in bits and pieces cleaned out of the system.
Old 07-20-2005 | 11:57 AM
  #9  
zoom44's Avatar
Administrator
 
Joined: Jul 2002
Posts: 21,958
Likes: 115
From: portland oregon
In light of the upcoming recall and possible confusion concerning flash levels for 2004 cars and 2005 cars I thought this would help some:


2004 car flashes started with SW-N3H(5 or6)Ex where 5 or 6 is AT or MT and the letter after the E is the level. that was until the N flash. for awhile everyone talked about a second Mflash remember? that was because they changed the 2004 flashes to this SW-N3Z(1 or 2)Ex with 1 or 2 being AT or MT and the letter after E being the level. the first "Z" flash released was also M. this was them saying " we are no longer on 1.xx but are now on version 2.0" but there was a WDS software bug so they had to make a new one and we got the N flash. which is for all practical purposes identical to the "H" Mflash.

now 2005 cars have their own flsh numbering and it is split into AT and MT as well as US FEDeral and Canada cars as one group and California emissions cars as a second group. so there is now 6 flash numbers between all RX8s in NA:

2004 A/T N3Z1-18-881N SW-N3Z1EN000 All
2004 M/T N3Z2-18-881N SW-N3Z2EN000 All
2005 A/T N3K6-18-881C SW-N3K6EC000 Fed/Canada
2005 M/T N3K7-18-881C SW-N3K7EC000 Fed/Canada
2005 A/T N3K8-18-881C SW-N3K8EC000 California
2005 M/T N3K9-18-881C SW-N3K9EC000 California

the letter after the E is still the flash level and as you can see by this list the "N" flash is the equivalent of the 2005 "C" flash. they have released a new version for each group each time. So Pflash was equal to 2005 D flash etc. there may not even have been a change to each group each time but that they want to keep them moving at the same time to keep it simpler for themselves and the techs in the field.
Old 03-18-2008 | 12:06 PM
  #10  
zoom44's Avatar
Administrator
 
Joined: Jul 2002
Posts: 21,958
Likes: 115
From: portland oregon
most current PCM calibrations according to MSP16

Year / Transmission New PCM Calibration Part Number File Name
2004
M/T - All N3Z2-18-881U SW-N3Z2EU000
A/T - All N3Z1-18-881V SW-N3Z1EV000
2005
M/T - Calif. N3ZD-18-881H SW-N3ZDEH000
A/T - Calif. N3ZC-18-881J SW-N3ZCEJ000
M/T - Fed. N3ZB-18-881H SW-N3ZBEH000
A/T - Fed. N3ZA-18-881J SW-N3ZAEJ000
2006-2008
M/T - Calif. N3M1-18-881K SW-N3M1EK000
A/T - Calif. N3M2-18-881M SW-N3M2EM000
M/T - Fed. N3M5-18-881K SW-N3M5EK000
A/T - Fed. N3M6-18-881M SW-N3M6EM000

We would normally call this the "U" flash since we generally speak of flashes in terms of the 2004 MT flash
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
RevMeHarder
New Member Forum
6
08-16-2023 07:23 PM
JimmyBlack
Series I Major Horsepower Upgrades
273
02-10-2020 11:23 PM
ErwinN
Series I Tech Garage
1
09-23-2015 10:29 PM
Forevermore
Series I Trouble Shooting
6
09-20-2015 02:04 PM



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


All times are GMT -5. The time now is 09:26 AM.