Got a weird 9.70 AFR

[frankc730]

So I was driving home tonight was mostly highway driving did a pull going on the on ramp and then set cruise control the whole way I wasn't watching my ap but my AFR hit 9.70. Now I must say I dnt know a whole lot about AFR but I've never seen it go to 9.70 and the pull wasn't even to WOT so idk it was just for a split second cause. The whole rest of the ride it would go to 11 something. Is this something I should worrie about ? I'm gunna do some logs on my ride to work tmmrw to see if it happens again

[Agent_Orange]

Probably SWAS.

If you accelerate hard with the right amount of steering input the ECU will dump fuel to cut power to the wheels.

[frankc730]

I did whip around that on ramp pretty quick could be why. Now if I was running lean what numbers would I see. Just for future refernce

[nilashish]

Higher AFR numbers mean you are running lean and lower means you are running rich

[frankc730]

Well what's too high ? Anything past 29 basically

[Fjager]

you get 29 when you are decelerating using engine braking, it's the engine saving fuel basically, you would have to pay attention to the gauge while driving and if you see anything over 15 it is lean for normal driving around, depends on your tune tho, your tuner could do that on purpose. depends really on your tune what would be considered lean.

[frankc730]

Cobb stage 1 with IC

[punkk77]

If you are referencing 9.70 as the lowest reading on the AP while viewing AFR, im pretty sure you're okay. I had the same thing happen, but the wot log shows me around 11.4 at wot. Just take a log and check it out, it should put you at ease.

[Danfriscia3]

like stated before, swas. Especially considering you came around a turn.

your afr's should be around 14.70. the only time it goes up to 29 is when decelerating

[bryancregger]

Originally Posted by Danfriscia3 like stated before, swas. Especially considering you came around a turn. your afr's should be around 14.70. the only time it goes up to 29 is when decelerating

AFR should not always be around 14.70. WOT should be tapered around 11.5 or so. If you are seeing 14.7 your tune is either fucked or your wideband is faulty.

[Danfriscia3]

Originally Posted by bryancregger AFR should not always be around 14.70. WOT should be tapered around 11.5 or so. If you are seeing 14.7 your tune is either fucked or your wideband is faulty.

Correct. Should have specified.

[Chron]

I routinely drop into the 9's for a few cells during 2-3-4 WOT logs when I get back on the throttle from a shift, but I already run decently rich because of shitty CA gas. Dropping into the 9's every once in a while is fine. Now if you were consistently running in the 9's, that would be a different story!

[Hargarbl]

You will drop down when you shift when you push the car. Watch it one time on a nice safe open straight road. Give a quick second or 2 ( or 5) of wot and push the clutch in and watch your afr, I can guarantee it will drop down to low 10's or even 9's after you push the clutch in. It's completely normal and nothing to worry about, as long as your wot logs show where they need to be you have nothing to worry about. I remember reading about it before, what causes it and all that but I don't feel like searching for it (maybe op could do that instead). Or maybe we could get someone like @Lex; to chime in on it.

Also, I thought SWAS cut fuel in order to cut power, that would cause a lean condition.

[JgamB]

Originally Posted by Hargarbl Also, I thought SWAS cut fuel in order to cut power, that would cause a lean condition.

All of the information I've seen regarding SWAS intervention points to rich fueling conditions, and I've heard everything from reduced boost targets, retarded timing, and reduced WGDC. It's probably some combination of the above.

I would assume the same thing that's already been mentioned - going rich from open loop to a shift, and nothing to be concerned with. A 2-3-4 log would probably be a good method of taking a closer look.

[Hargarbl]

Originally Posted by JgamB All of the information I've seen regarding SWAS intervention points to rich fueling conditions, and I've heard everything from reduced boost targets, retarded timing, and reduced WGDC. It's probably some combination of the above. I would assume the same thing that's already been mentioned - going rich from open loop to a shift, and nothing to be concerned with. A 2-3-4 log would probably be a good method of taking a closer look.

Yes you are correct. Just did some quick research, looks like swas controls boost which could cause a rich condition.

Op, do a 2-3-4 log, shift easy, not slow but not power shifting either. I bet you will see your afr dip down (rich) between shifts.

[Agent_Orange]

Originally Posted by Hargarbl . Also, I thought SWAS cut fuel in order to cut power, that would cause a lean condition.

Look at a log from confirmed SWAS intervention.

IDC% will spike UP quite noticably.

[Lex]

The only time AFR gets to the 9s is either from SWAS/traction control or from a big boost leak.

[btstarcher]

I dip to around 9 every time I shift, because HKS in VTA configuration. Love them afterfires!

[JgamB]

Originally Posted by btstarcher I dip to around 9 every time I shift, because HKS in VTA configuration. Love them afterfires!

Happens to cars with OEM and full recirc BPVs also. (not my log)