P2096 - Downstream Fuel Trim System 1 Lean.

 

That code means your downstream o2 sensor is reading lean. Could be a bad sensor or an exhaust leak by the cat.

Have you done anything recently to the exhaust?

 

Not to the exhuast. i put a drop in n&n... can this explain my tereble gas mileage, 12mpg with 33's and 4.10's ?

 

How long have you had the K&N when the code popped up?

 

About a month... Where is the sensor at? Is it something I can replace?

 

Here is some information on the code you have. Each item in the list of possible causes has quite a few things to check.

[h=2]P2096-DOWNSTREAM FUEL TRIM SYSTEM 1 LEAN[/h]

• When Monitored: With the engine running in closed loop mode, the ambient/battery temperature above -6.7° C (20° F) and altitude below 2590.8 m (8500 ft).
• Set Condition: The conditions that cause this diagnostic to fail is when the upstream O2 sensor becomes biased from an exhaust leak, O2 sensor contamination, or some other extreme operating condition. The downstream O2 sensor is considered to be protected from extreme environments by the catalyst. The PCM monitors the downstream O2 sensor feedback control, called downstream fuel trim, to detect any shift in the upstream O2 sensor target voltage from nominal target voltage. The value of the downstream fuel trim is compared with the lean thresholds. Every time the value exceeds the calibrated threshold, a fail timer is incremented and mass flow through the exhaust is accumulated. If the fail timer and accumulated mass flow exceed the fail thresholds, the test fails and the diagnostic stops running for that trip. If the test fails on consecutive trips, a DTC is set.

[TABLE]
[TR]
[TD="bgcolor: white"]Possible Causes
[/TD]
[/TR]
[TR]
[TD="bgcolor: white"]EXHAUST LEAK
[/TD]
[/TR]
[TR]
[TD="bgcolor: white"]FUEL DELIVERY SYSTEM
[/TD]
[/TR]
[TR]
[TD="bgcolor: white"]O2 SENSOR, WIRING, OR CONNECTORS
[/TD]
[/TR]
[TR]
[TD="bgcolor: white"]ENGINE MECHANICAL SYSTEM
[/TD]
[/TR]
[TR]
[TD="bgcolor: white"]POWERTRAIN CONTROL MODULE (PCM)
[/TD]
[/TR]
[/TABLE]

 

Changing the sensor may not fix the problem. It could be as simple as an air filter, fuel filter or the throttle body needs cleaning. Personally I would start with the routine maintenance items before I started throwing parts at it.


Unfortunately I don't have a service manual to tell me which is bank 1 and which is bank 2 (or system 1 / system 2). Typically bank 1 is on the left side of the engine, but again I am not positive on the JK.

The o2 sensors will be physically mounted in the exhaust system. Your upstream sensors will be just before the catalytic converters and your downstream sensors will be just after the catalytic converters.

These sensors can be a PITA to change. You will need a special socket so the wire is not damaged (see photo).

O2 sensors should run you $20 - $30 each.

 

Bank 1 is on the right side of the engine. Bank 2 the left side.

Left and right is from the driver's point of view when sitting in the driver's seat.

 

Thanks a lot for all the info, I'll start with oil change this week and see what happens from there.