Tooled around tonight doing some data logging, but discovered that my OBDII connection is reporting "NO DATA" for my Short and Long Fuel Term Trim on Bank 2. It even reports that those PIDs are not even supported.

Does anyone know if our ECU separates Bank 1 and Bank 2, or just lumps them together? 1998 5VZ, if that matters.

Everything I've read suggests that a V6 should be reporting Bank 1 and Bank 2. But at the same time, I'd expect some serious complaining from the ECU if there was a Bank 2 malfunction.

(On the upside, at least the Bank 1 trims looked well within spec. )

If it had a O2 sensor for each bank I'd expect to see a bank 1, and bank 2.


With only 1 O2 sensor I would not.

Hopefully this clears up your confusion. Many V style engines use a total 3-4 of oxygen sensors. The 3 sensor setup would include 1 oxygen sensor at each exhaust manifold (total of 2) and 1 oxygen sensor behind the shared catalytic converter. A 4 sensor set up would typically be found on a true dual exhaust with at least 2 converters hence the additional one behind that other cat. These set ups allow for the 2 separate bank fuel trim readings because each bank (side) is monitored individually.

Again above describes many...probably most V style engines but NOT ALL.

However your 4runner should have a total of only 2 sensors. One in front of the converter and one behind it. This is monitoring both banks (sides) at once because they join before the sensor. Therefore you have only one bank
in scan data and it is totally normal on this engine. I'd be more concerned if you were magically picking up data from the mysterious bank 2 lol.

Outstanding, thank you!