Really new to learning engine/ecu parameters. High AFR like 95% of the time

So I have an 04 cobra, pullied w/ JLT Ram air, and catless exhaust. I've been driving it like this for a year or more.
Now, fast forward to today and I've installed a canned tune from Bama for 91 Octane, along with an Innovate Wideband. What worries me is that driving around normally I'm anywhere from 17-22 in the red. I thought it was my weld job, and that I had a hole somewhere so I replaced exhaust gaskets, rewelded the bung, and checked for leaks using a light. It looks good. My AFR does drop while in boost, but I haven't hooked up a data cable to it to log. Frankly now that I have a giant blinking gauge at eye level I haven't beat on it like I have in the past.
I have zero trouble codes, and replaced the vacuum T with new lines behind the supercharger.
I have also provided a small window of a tiny 4th gear pull to see if it could be something other than too much air, and possibly fuel related? I haven't investigated what is normal for the fuel ranges quite yet. Which is why I'm asking for someone more experienced with these things to please take a quick look. -Thank you!

First, ditch the Bama tune. It's well known they suck. Second, get the analog set up in your tune. It'll be a lot better when you can see what's going on in the log with the A/F.

For your STFT's you usually want to see within 5% of stoic (.95-1.05). At least that's what I usually aim for. For WOT I like 11.5:1 for A/F. Some tuners like 12:1, but that's too close to the edge for me.

Does your wideband need some kind of calibration done? If it does make sure you do that as needed.

I calibrated the wideband according to the instructions. unplug, turn on, turn off after 30-60sec, plug in, 22.6 (max) with car off. I realize the bama tune sucks, but I am pretty limited on island lol. I reverted back to stock today and my AFR numbers haven't changed.

what size pulley? probably are running lean just from a stock tune with a pulley, no?

lol Bama tune

Hit up a tuner on here they'll get you dialed in. I use MalcolmV8 who's awesome others use 04sleeper, decipha they're all phenomenal. I think I'm forgetting one or two others

srdigital said:

what size pulley? probably are running lean just from a stock tune with a pulley, no?

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I cant find the receipt, but it is probabaly a 2.8-2.9. I feel like a pulley swap wouldn't explain why its avg. 17 at an idle and bouncing off of 22.4 under easy driving.


I reset the ecu back to stock last night to eliminate the possibility of it being the tune.
I'm going to get some easy miles going back and forth to work to see if the avg. a/f lowers at all.
I'll give it a few days and switch banks to see if it changes.

With the stock tune log your STFT and LTFT's. I'm going to guess they zero out pretty well. Unless something mechanically has been changed. Pulley size won't matter at idle and part throttle. If your fuel trims show close to lambda and your wideband is still giving weird numbers I'd say something is up with the wideband.

looking at my data table and trying to decipher it, but anything less than 1 is adding fuel, anything greater than 1 is subtracting fuel? 1 being perfect 14.7:1 A:F
using my 30sec data log to figure out the basics.
So, and if im reading this right, the lowest was .86*14.7=12.64, i.e. ecu is commanding more fuel. This was at 3348 RPM, while under some amount of boost, and reflects on my foggy memory of seeing my AFR dip in the 12s.


I do notice the difference between left bank/right bank after color coding everything.. Something is up with the left bank, which is where my wideband was placed in between the 02 sensors. The left side has more anomalies within the data.

What sort of conditions is that datalog taken from? Stock tune? Do you have any wideband data with it? Without that it's hard to make a good assessment of if the data is accurate.

looks like you have stock injectors and maf, if so reload your stock tune on and if the AFR is correct you know its in the tune. This adding more air because of the pulley will make you go lean is BS, thats not the case, but you don't want to be beating on the car with a stock tune because timing won't be what you would want.

Livelink isn't working on my laptop, so yeah i get it that its hard to see lol.
-The spreadsheet i posted was with a 91 tune from bama. Its been on the car for i would say atleast 2 years.
-I reset the car back to the stock tune, the AFR is still wonky. So I'm thinking its the wideband somehow.
- My "test" or, testing conditions are as follows. I take the same route home, 2 slight right turns and about less than 1/8 mile of freeway before my exit ramp.
at the 2nd right turn I'm in 4th gear, stomp it and let off at the ramp, hence the short data logs. it is always night time so temps are in the low 80s, same weather, same gas, etc. the goal is just to get into boost long enough to gather data while trying to use the same scenario every time.

I did the same "test" with the stock tune yesterday and just now looking at the data-log.