Hey i just got my tuner the other day it didnt have any maps on it so i downloaded a couple off the cobb website for the 2006 usdm mt i downloaded the stock map and the stage 1 map. i ran the stage 1 map for a day and logged the data and my AFR went from 11.0 to 21.0. so i loaded the stock map into the car and i got about the same numbers i will add the data log for the current stock map its kinda long i forgot to stop it when i parked. if any one could help me figure out these numbers and what the issue could be. the car has an hks legamax cat back and a racing beat duct to the stock box those are the only mods i know of on the car.

 

The stock wideband sensor cannot read below an air-fuel ratio of 11:1. Your log shows that you are at or below this point for nearly all parts of open-loop operation. This is fairly typical for stock maps, although you may be running a bit richer than average.

The Cobb stage one tune will not correct this, and it may make you car run dangerously lean.

The AccessPort does not correct the calibration of the ecu by itself, instead it enables a competent tuner to calibrate your engine. I highly recommend you seek out the services of MazdaManiac for a calibration made for your engine.

Alternatively, you can learn to tune for yourself with Cobbs AccessTuner Race software. Most people find this a daunting task.

I have done both, and learning to tune can be fun and satisfying. However, it has cost a great deal of time, and far more money than a professional tune simply in terms of the gas I've consumed.

OTOH, MazdaManiac will have your car running much better after you get your first calibration from him.

 

I don't know how you read anything of the log oltmann ....
My version of excel lumped all the data in to a single field in column A

edit:
Tried again to figure it out.
yeah its a mess .... all the numbers are jammed together ... can't tell what value is for what.

 

something strange is happening near the end of the log with the AFRs, Airflow, Load, etc. what exactly were you doing at that point?

highlight the first column, select data and then text to columns

 

Cool thanks.
The Cobb AP was used to acquire that data log?

Is that the way the new ones do it now?
Mine doesn't look like that.

 

Yeah... Were you coasting down and tapping the gas peddle every two seconds? If so, why? If not, you may have a problem.

 

Doesn't look too bad to me. Yes you are a bit rich but meh .... get Jeff to tune for you .... you'll love it.

The reason why you were at 20 AFR is because you had taken your foot off the throttle. The fuel goes off and the AFR's go up ... that's the way it works ... nothing wrong there.

Look at the throttle pisition why you got the 11's ... you were WOT with high load (almost 100%) .... check the fuel map out in that gear and you will like see that the map is in the 10's or something close to that.



I'm guessing the air conditioner compressor kicked on.

 

If I read his top post right ... ummmm it said something about forgetting to turn the Data Logging off once he came to a stop and there is some idle data there.

Is my guess

 

I suspect it was opened in WordPad or some other app, and saved with some extra formatting or characters. As a result Excel doesn't recognize it as a csv by default. I actually used MegaLogViewer, I like graphs for scanning complete logs.

 

yup, saving the datalog file after editing or anything overrides the csv format.

 

sorry about the bad file. I saved it and sent to a zip i looked at it only now it is really messy. I will upload a new one again if that will help. i dont know what happened at the end of the log. I wasent tapping the gas while i was driving only downshifts and a few revs to see what the numbers would do when parked. WCS you say these numbers are going to be ok to drive it the way it is my numbers were about the same with the stage one tune also but the car had some more pep. i would like to get MM to do a tune yet but there are a few parts i would like to put on this winter before i get it professionally tuned.

 

I re added the log and also put on the log with the stage one tune

 

It looks like the Stage 1 tune is actually doing okay on your car, but it is a bit difficult to tell. When logging, it is best to run the car from ~3000rpm to redline on level ground in the highest gear you can safely use.

Nothing in the Stage 1 log looks explicitly dangerous, it isn't really going to make great power, but probably better than stock. Two things to consider: the AFRs could get leaner over time, and because of the timing split used in that calibration the car will be more susceptible to detonation if that happens.

 

20.9 is what u will see no matter what if your not on the throttle.... Anywhere between 10.5 and 16 is what you could probably see when your at part throttle. Chances are OP didn't know afrs don't stay constant and when there is no fuel being injected (ie zero throttle) the afr gauge will max out at 20.9 be happy your cobb stage 1 is running rich at wot and not lean.

 

So I agree with Oltmann and Rotary .....
(@ Rotary ... I mentioned the foot of the throttle thing in post #7 )

I would like to add however ....

Log file submission etiquette:
1) You should run a log file for a specific purpose
a. Idle log
b. Cruise log at a intended rpm level (4000, 4500, 5000 rpm etc) and make sure you know what gear you used. You need to this to compare to the Fuel Map
c. WOT Log file and gear

2) Label the file as such so we know what to expect without having to look at file.

3) LTFT and STFT readings of -0.16 = 0 its just one of the funny things the Cobb does.

4) 69.69 Is how the Cobb AP logs the Throttle Position fully open

5) It's important to know if the car is in Open Loop or Closed Loop

Edit:
Just sooo you know ... I'm not a pro-tuner, what has been offered here please take it for what it is.
I would also like to add that I think I recall from MM's tuning webinar that it's not that easy to make a NA Rensis have knock or detonation.
You need relatively high loads and a Lean condition. I would guess something North of 75% load and AFR's above 16.
(my guess)

 

I think that is correct, detonation isn't a huge concern for NA rotaries. However, the Cobb stage1 calls for 14.7:1 with at the torque peak with 5 degrees of split. Fortunately, OP isnt getting that, because those or not conditions amenable to a long engine life.

 

Thanks for the knowledge. I just ask simple questions now early on so i dont end up having huge problems later and you guys here seem to have the knowledge needed for most everything. I was just curious about the afr reading because i read on cobb site the numbers should stay around 14.7 +-.6. I wasent sure if that was at certain speed or throttle position. Thanks again

 

Wow ... post a link to that because .... well it's wrong.
The AFR's cannot stay at 14.7 ... they just don't

Maybe they meant 14.7 at idle or something? Or closed loop cruise?

 

My bad WCS you got me heres what i read. I seem to have just read what i wanted at the time and scared myself a bit

 

Comprehension fail

 

I admitted I was wrong if I was always right I wouldn't need the forum help. At least now I know a bit more of what to look for and how to do it properly. Thanks for that