trd07tc

iTrader: (-1)

Is there a max range with the MAF?

Where does the ECU read the AFRs from?

waiting on boost control before I consider this unit

cburglb34

ecu reads afr from the front a/f(o2 sensor) MOST PEOPLE KEEP THINKING THIS IS A O2 SENSOR WHEN ITS REALLY A WIDEBAND SENSOR... and ours is top notch it gets great precise readings..


boost control your gonna have to wait on for some time buddy....=} i like your build

crush02342002

iTrader: (2)

its not exactly a wideband, one might call it a hybrid...correct me guys if im wrong but its not a normal nernst cell 02 sensor that operates on a 0-1 volt range like the secondary o2 sensor, I beleave it works on a 0-5volt much like wideband but not as accurate and built differently.

3min3m2

Beautiful minus the price tag.

But ya gotta pay to play right??

ScionFred

iTrader: (1)

As I understand it, our Denso AFR sensor is a typical current flow switching nersnt cell O2 sensor with detection cicuitry that outputs a signal voltage between 0-5V just like the Bosch sensor used by the AEM UEGO.

Using Palmer ScanXL software to monitor my Denso AFR sensor indicates that it is at least as fast and accurate as my UEGO. Unfortunately the readings I get with ScanXL are in lambda which I find more difficult to interpret. I can also read the voltage which is 3.3V at 1.0 lambda (stoich/14.7:1). Lower voltage = richer and higher voltage = leaner.

Here is a good link for more info on O2 sensors:

http://www.autoshop101.com/forms/h37.pdf

t_urbo_C_harged

Crush, I believe it operates around 3v's. Someone was describing it to me a long time ago (reputable source) and I don't remember exactly but it isn't 0-5v like a normal wideband.

t_urbo_C_harged

or I could be wrong! lol nice info scionfred.

paul_dezod

Fuel trims can not be ignored when setting up the correct injector "correction". The steps below are how things need to be done to prevent any ECU relearning with this unit.

1) an OBD2 scan tool with fuel trims needs to be used.
2) Put new injectors in car
3) Put best guess of flow rating into software
4) Flash ecu with new cal
5) Start car and let idle for 1 min
6) Look at LTFT, try to adjust value of new injectors to get it closer to or between 0 to -5
7) Reflash ECU
Drive car at steady state at 45mph adjust value again to be LTFT between 0 and -5
9) Reflash ECU
10) Drive car at steady state at 65mph adjust value again to be LTFT between 0 and -5
11) Reflash ECU and drive!

cburglb34

wow nice infor paul btw does the 45 , and 65 mph thing work when tuning a aem fic also like to determine fuel trims

thendawg

iTrader: (2)

Haha im using scanxl also - if I set my wideband to lambda - the front 02 readings and my wideband are dead on - now if there was just a way to make scanxl convert it to afr based on a defined stoich (1.000 lambda) value....

paul_dezod

Yes. Same procedure.

cburglb34

ahhh......hmmmmmmmm sweet thanks paulie =] haha jk

paul_dezod

Welcome

SB08tc

Paul, say I got a unit today. How long would it take you all to recalibrate it for 700cc injectors and ship it to North Carolina?

ScionFred

iTrader: (1)

I was initially hesitant to pay $85 for ScanXL with so little feedback available on OBD2 software but it's proven to be worth every penny. Besides being able to monitor all of the relevant engine OBD2 PIDs, the data logging and graphing features have been invaluable. If I had a integrated carPC and could either learn lambda or convert it to AFR, I wouldn't even need a separate UEGO gauge.

Before buying my UEGO I looked hard for a gauge that could connect to the oem O2 and found none. Pity... it would be very easy to make one and sell it for half the cost of the UEGO or alternative AFR guages. Plus there would be no need to weld in a separate bung for a duplicate WB O2 sensor.

BTW, as Crush wisely recommended to me, it's best to monitor idle fuel trims with a warm engine for tuning purposes. My idle fuel trims vary a lot between cold and warm. They also vary a lot between idle, 45mph and 65mph but what you want is to find the average and an injector correction factor that works well in all 3 conditions. Idle being the least important as long as you don't have idle problems.

DezodDon

Yes your fuel trims will vary between cold and warm as the ECU enters into closed loop only after lighting off the Catalytic converter, reaching a predetermined coolant temp, and after a certain time.

PS, sorry for not getting back to you the other day, paul decided to do testing in house rather that put you through any problems if there were issues to arise.

paul_dezod

We are about 1-2 weeks out on this unit. I can get a cal close on 700cc injectors, but it may need to tweaked some on your end.

paul_dezod

The stock Toyo ECU looks at those three points as "trigger" values for learning processes of fuel trims. Idle is first and usually takes about 45-60 seconds of idling even off of cold start to begin evaluating the learning process.

In short, all 3 positions, per several Toyo Engineers are important.

SB08tc

Ok, thanks Paul. I am getting the money together to get this unit within the next couple weeks. cant wait to see how it differs from the AEM EMS.

ScionFred

iTrader: (1)

I don't know if my XB2 ECU is that different from the TC's or if the difference is OBD1 vs OBD2 but even on the coldest days my ECU enters CL as soon as the primary O2 sensor warms up (~1 minute). Even then, my cold engine fuel trims are very different from my hot engine trims. It seems to me that the ECU uses different fuel tables or makes adjustments when cold vs hot. That might explain why a CL cold idle FT of -15% becomes +15% when hot. Then again, it could be caused by other factors as well. I'm unsure. I know what I've seen and data logged but am still working out the cause and effect.

I'm sorry I didn't realize it was you that I spoke with the other day. NP on not getting back to me before and I understand why you would want to do the testing in-house. I'm not exactly close by and any problems would have to be handled by phone calls and emails. But if you guys ever change your minds, I'd be very happy to test the X-1 on my XB2. The X-1 is what a piggyback should be and not like the weak piggyhacks currently available for Toyotas.