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2009 Avalon XL
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231 Posts
Discussion Starter #23
Whoa! What program did you use to be able to log the data this way? I see something about 'ecuEdit_OBDCan'. Is this part of TorquePro or something else? I'd love to graph information like this.
The program is called EcuEdit. Its not cheap, but it is awesome for logging. You will need a laptop for the program. I don't know if it works with a bluetooth obd2 adapter or not. I have a wired tractrix 2.0 cable.

http://www.epifansoft.com
 

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Slow 2010 RAV4 Sport
2010 Toyota RAV4
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279 Posts
Here's a better look for our tech heads :nerd:

Notice that no matter the situation, the afr never goes below 12.08 or above 18.12. Not one bit. That's why I think the that is just the limits of what the sensors and/or ecu can "measure" and the actual afr at WOT is actually quite a bit lower. It has to be. Even if the 12.08 is the somehow lowest afr the car could achieve despite the targets, no way it would hold a steady 12.08:1 ratio throughout the entire rpm range.

As far as my ocd is concerned, as long as the numbers are accurate between 12.08 and 18.12, its ok. I obviously want to keep well within that range anyway. Hopefully,
my next tune leans the car up a bit.

I can't stop looking at your data. I think what's interesting about this one is your commanded air/fuel ratio at wide open throttle (WOT). Why does the commanded air/fuel ratio get richer and richer and then jumps back up and get richer and richer again? I mean, it's seeing something else besides the air/fuel ratio to command it to keep getting richer since the air/fuel ratio stops at 12.08:1. It has to be going off of the O2 sensor or a combination of things to decide to keep going richer. It's like it knows you need more fuel despite showing the air/fuel ratio stopping at 12.08:1. It keeps commanding more fuel all the way down to 10.0:1 or so. I am assuming it is starting leaner at the beginning of the rpm band and getting richer as the engine goes through the rpm band.
 

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2009 Avalon XL
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231 Posts
Discussion Starter #25
I can't stop looking at your data. I think what's interesting about this one is your commanded air/fuel ratio at wide open throttle (WOT). Why does the commanded air/fuel ratio get richer and richer and then jumps back up and get richer and richer again? I mean, it's seeing something else besides the air/fuel ratio to command it to keep getting richer since the air/fuel ratio stops at 12.08:1. It has to be going off of the O2 sensor or a combination of things to decide to keep going richer. It's like it knows you need more fuel despite showing the air/fuel ratio stopping at 12.08:1. It keeps commanding more fuel all the way down to 10.0:1 or so. I am assuming it is starting leaner at the beginning of the rpm band and getting richer as the engine goes through the rpm band.
Well, according to DannoXYZ, "Typically mid-range RPM AFR is leaner for quicker-response and torque. Getting richer in the upper-RPMs for safety."

OVT also mentioned about not raising the afr too high for safety reasons. I'm sure he was worried about heat and pre-detonation at high rpm. But you raced your Rav4 for years with a much more stoiciometric afr at wot with no problems. With stock manifolds and cats even. Though obviously tuned differently from the factory, our engines are mechanically the same.

R9k tuned brought your afr a lot lower though. I definitely won't assume to know more than them. What is your commanded afr at wot now? I wonder if they had to lower it to run the more aggressive timing.
 

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Slow 2010 RAV4 Sport
2010 Toyota RAV4
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279 Posts
R9k tuned brought your afr a lot lower though. I definitely won't assume to know more than them. What is your commanded afr at wot now? I wonder if they had to lower it to run the more aggressive timing.
I guess I'll have to make a run tonight somewhere to find out. Any other parameters you interested in? I'll add it to the video screen if it is available for me to add for viewing.

And for the record, anyone reading this thread, I run 92 octane ALL THE TIME. I don't want anyone to assume I'm running intake/exhaust mods like this all year round without knowing this safety measure. I am sure Moondogg does the same. The ignition is more aggressive with running higher octane. I know because I tested it but not sure if I documented it anywhere here. If you have a Weapon R intake, especially with that crappy Weapon R filter, be advised that my air fuel ratios at wide open throttle was stupid/ridiculously lean. Like 14:0.1 - 16.0:1 or so. I believe I did document that when doing dyno runs with it. And gained NO hp over stock intake, using the Weapon R air filter.
 

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2009 Avalon XL
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231 Posts
Discussion Starter #27 (Edited)
Myxalplyx, i was just watching your Honda Pilot intake comparison video, and i noticed that you pilot measured an afr much lower than 12.08:1. So i did nome googling and saw that it uses a 5-wire o2 sensorn instead of 4 like our toyotas. That lead me to this...

"Different sensor technology. In general:
-- 1 wire sensor is old-school, just a signal wire with the ground coming from the exhaust itself
-- 2 wire sensor added a separate ground wire for a cleaner signal
-- 3 wire sensors added a heater circuit and both the heater and signal share a ground
-- 4 wire sensors have been the norm for a while and you basically have 2 circuits -- 2 wires for the heater, and 2 wires for the signal (adds dedicated ground to the 3 wire)

Recently, there have been more 5-wire sensors which are actually wide-band type sensors (as opposed to a simple "rich/lean" switching sensor). These sensors utilize a pumping current and different control scheme than the "simpler" switching sensors which simply generate a voltage based on O2 content....

Basically, if you've got a 5-wire O2 your car is running a wideband front sensor and you need to replace it with a similar sensor..."
Our o2 sensors are definitely no narrowband since they read 0-5v, but i assume they dond have the sam range as 5-wire air/fuel sensors either. Which further explaind the 12.08min-18.12max readings we get.
 

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Senior TN Member
Porsche
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7,508 Posts
Hmm, certainly looks like some sort of hard limit/edge on the charts for AFR. I wonder if this is car with simulated O2 output that's scaled back up? Some wideband sensors on Toyotas had their outputs scaled down to fit within 0-1v range mandated by OBD-II standards. The scan-tool would scale it back up for display, but you lose range and resolution in the process.

Could also be problem with heater-circuit as that will throw off calibration, but not throw a code. Toyotas use higher-temp 1200-F heater compared to other wideband sensors. May want to check that heater-circuit is drawing 5-7amps. It may still work at the 3-4 amp draw of other sensors, but the numbers may be off.

Another very slim possibility is someone installed an older 4-wire narrowband sensor for the upstream sensor. It's possible since the connectors are similar.
 

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Registered
2009 Avalon XL
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231 Posts
Discussion Starter #31
Well bank 1 sensor 1 is the original sensor that came on the car. Bank 2 sensor 1 is only about 2 months old and a different brand...

https://www.amazon.com/gp/aw/d/B000C8ZJN8/ref=yo_ii_img?ie=UTF8&psc=1

I measured both banks individually and both top out at 18.12 and bottom out at 12.08. Also, myxalplyx is displaying the same range with the measured afr in his rav 4. So, i think its safe to rule out wrong or faulty sensors.
 

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Honda-Tech White Ops
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1,581 Posts
Well, Compared to a Bosch LSU 4.2 or 4.4 WB sensor that goes to 8 and leans at 22, theres no way to determine if this is the min-max of these sensors you have..
 
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