Gernby

The issue with the O2 on the '06+ is that the sensors don't all have the same response curve below 14.7. The AF Corr value is a correction that works well for the average sensor, but not for all. I've seen some S2000s that have sensors that read much leaner and some that read much richer than average. That's why I calculate the actual correction factor for each sensor as part of my eTuning process.

MorngWoodStewie

This thread should be stickied, I think I learned more on this one page then ever on a single thread and it being 10 pg.s

King Tut

How do you do that without any truth data from a known good wideband aftermarket sensor?

Gernby

That's one of the few things about my tuning process that I like to keep to myself, since I'm not aware of any eTuners that do it at all. It seems that everyone just assumes the AF Corr value is correct, and uses it blindly. This works out fine for an "average" S2000 with an O2 sensor that sits in the middle of the range, but it sucks for the rest.

What I will say is that it's not hard to solve for an unknown variable if all related variables are known. Basically, you don't have to compare the OEM O2 reading to a "known good" O2 reading IF the other related data is correct.

flanders

Have you checked your method against external wideband sensors on lots of different cars?
I find it a bit hard imaging all other variables to be constant enough.

Nash2984

Recently installed Kings Performance stage one kit
5858 precision turbo
Aem high pressure fuel pump/rail
1000cc ID injectors
Fuel return kit
700hp KP clutch
Hondata flashpro
Mac boost selonoid....

Took the car to a tuner, 400hp to the wheels and 286 lbs torque

The car ran great for 2-3 weeks but then yesterday I've noticed lost of power if I step on it, probably around 5000rpms! Also noticed that my afr aem guage spikes up to 16-17 when on wot and before I notice the loss of power..

Thought I had a vacuum leak somewhere and that's y it was running lean, so I replaced all vacuum hoses that go on the intake... Checked all the fittings, connections everything seems to be fine!

Did anyone experience something like this before? Anything else that could cause this to happen?

Thanks in advance!!

s2000Junky

One or two runs at that lean and you can definitely blow the motor, be careful. Contact your tuner and dont drive the car anymore or at least stay out of boost until you can get resolved.

chrisaltima

Just some quick input. I was running a Hytech header / TP last season. I ran the car with plenty of WOT in the canyons, for about 3 seasons; un-tuned. This resulted in me burning a valve due to the car running so lean at WOT. After I rebuilt my head and reverted back to the OEM header / Berk TP. The car runs so much better overall. As Junky said our OEM Header is truly great. The Hytech did shine in the high range.

Basically what I am saying if you are un-tuned it may be a good idea to stick to the OEM header. I learned the hard way.

_ju5t1n_

Wouldn't the test pipe be a bigger factor in causing it to run lean?

s2000Junky

Typically. Few headers flow better then stock.