Narrowband & Wideband Air Fuel

I was searching the world wide web to understand if I could simply replace one of the stock narrowband O2 sensors with a wideband sensor on the stock exhaust manifold without having to install a new bung. I would choose the drivers side sensor to replace.

I came across several sources of information, but none directly speaking to the Tacoma. Specifically this product from Innovate: The LC-1. http://www.innovatemotorsports.com/products/lc1.php

Here: States they removed a stock narrowband and installed wideband with a narrowband simulation controller.
http://www.hptuners.com/forum/showt...ller-with-Narrowband-Simulation&highlight=plx

I guess my question to some of you here is, would this work with the Tacoma? Could I install the wideband O2 LC-2 sensor in the stock exhaust manifold and have the simulator send the narrowband accurately to the PCM/ECU?

Or should I have a bung welded to the stock manifold? But I didn't really want to add another flow impeding device into the exhaust stream.

 

Your Tacoma has a WRAF sensor, or Wideband Ratio Air Fuel, in each exhaust bank. If you remove either of those, your truck will not run right.

To monitor, you need an OBDII scanner of some sort which can read the factory sensors, or an aftermarket gauge/sensor. With its own bung added in.

 

Ah, so it already has wideband O2 sensors...?

I just need to interpret the volt reading with an ODBII device? This I can already do, read the voltage on the bank sensors. Just need to determine what voltage equals what A/F ratio.

 

ScangaugeII, can read the sensors, and show as rich as 12:1. No richer.

Ultragauge I believe can as well, but I do not have one. Most accurate and responsive way is with a standalone gauge, like the Innovate.

 

Regarding reading the Short Term and Long Term fuel trims and O2 sensor voltage through the ODBII ports...are these only accurate or valid in closed loop mode or also open loop (WOT) mode?

Does the ScanguageII read open loop A/F ratios as well?

 

You are making yourself too confused.

AFR is just the measure of the ratio of air and fuel in the exhaust. Independent of the Open or Closed Loops.

With an aftermarket gauge in the exhaust, you'll be able to tell how rich or lean the engine is running, under various conditions, "loads".

Using the Scangauge2 as an AFR gauge is not as accurate as an actual AFR gauge. It won't read as quickly, nor display the full range of the AFR's that the engine is running.

If you have boost, it is highly recommended to get an AFR gauge installed.

Cruising ~ 14.7 AFR. WOT ~ for boost 11 - 11.5. The TRD reflash usually has it around 10.5.

Cats will lean the mixture reading of a tailpipe AFR gauge.

 

Possibly, - and I get this. I am able to read some perimeters during closed loop but the PCM ignores the O2 sensors during open loop WOT and runs the trims on predetermined fuel maps/flash.

Meaning that, my readings are useless at WOT...unless as you state, I go the optimal/recommended route and install a separate AFR gauge and Wide band to more accurately read A/F ratio's to determine if I am truly too lean/rich or not at WOT. I suppose I need to do this if I ever plan on the MAF calibrator.

But yeah, I think this answers my questions. Thanks.

 

theres a PLX devices vid out where they replaced the factory o2 sensors with the bosch sensors, and using resistors/splicing, was able to both send the ecu needed narrowband/wideband as well as the module/gauge.

ive done this before with my honda, where the only o2 sensor i had was a wideband that was spliced into the factory harness. hondata forums had a complete walkthrough on how to do that, but will be different to our toyotas.

so to answer your question, yes there is a way but its beyond me how to go ahead and do it. the only advantage to this would be when sending your standalone ecu the wideband voltahe needed to datalog. when you have a wideband setup by itself, you are forced to keep up with watching the afr per rpm and its a trial and error thing to find a good tune. when linked to your ecu, you could record everything (datalog) and have a decent tune after 2-3 runs.