utkinpol

Hi,

Can anybody help me with this stuff - I got this CEL upon secondary air system coming to 'ready' state after I swapped back from softronic to original ECU code. No other CELs came, just this one.
It is a consistent code, I think I had same exact issue in 2011 when I tried to revert to stock code last time, car obviously runs great on softronic tune and on stock tune as well, there are no indications whatsoever that a mix goes too lean or too rich, there is no soot, etc. And, again, there are no other codes, at all. Just this one.

so it must be O2 sensors acting up, I presumed. Now I got stuck with a question - which O2 sensors? Softronic as any other tune ignores after cat O2 sensors so I presumed it is a first suspect but as I started googling about this P2196 code in all references it points to a pre-cat sensor.
It does not make much sense as both stock and softronic codes rely on accurate data from pre-cat sensor.

So, does anybody here know for sure - what sensor does P2196 CEL points to? pre-cat or after-cat?

Also, can anybody tell what actual voltages should come from O2 sensors, say, at idle and at 3K rpm? I can use durametric to check what do I get from my car.

Spiffyjiff

not sure if youve seen this but it does mention up/down stream...

P2196
Lambda correction downstream, bank 1 – rich/lean control limit exceeded

NOTE
--Diagnosis detects a deviation between the lambda value measured by the oxygen sensor upstream and the value measured by the oxygen sensor downstream.
--The deviation is eliminated through adaptation, a fault is only set once
the adaptation limits are exceeded.
--The most common fault cause is a leakage between the two oxygen sensors, resulting in the sensor downstream measuring more residual oxygen in the exhaust than the sensor upstream.

Diagnostic conditions
--Engine running
--Oxygen sensing upstream active
--No fault for secondary air injection, catalytic converter or tank vent
entered
--No faults detected for oxygen sensor or oxygen sensor heater up and downstream

Possible fault causes
--Leakage in exhaust system between the two oxygen sensors
--Oxygen sensor upstream faulty (contaminated/aged)

utkinpol

right.
I ordered upstream o2 sensor from pelican, and as usual after the fact searched web again and found this sensor, $100 cheaper.

http://www.jcwhitney.com/aem-5-wire-...8y2006g219u0j1

no idea if it is any good but it looks exactly like one on pelican parts web site. heck with it.

paradigm79

utkinpol,

Any resolution to this? I am seeing a similar problem after the factory catalyst (complete header) was replaced. Trying to determine if the rear O2 is causing it due to an oxygen leak or if the front O2 was possibly contaiminated during the work.

sightlinereaders

Had this same CEL issue: Dealer seemed unsure what the issue was and wanted to replace O2 sensor on bank 1, sensor 1. At dealer prices I passed on the repair and took to an independent shop for a look. They found that when the air filters were replaced, the duct from the air box to the throttle body was installed incorrectly allowing air to leak into the throttle body from a gap. They reinstalled the duct properly, reset the light, and voila- and couple thousand miles later, problem solved. Good luck.

www.sightlinereaders.com