P2099

Test 1 - Test 2:

Test 3 - Test 6:

SYMPTOM
P2099-DOWN STREAM FUEL TRIM RICH BANK 2

TEST NOTE
This symptom is diagnosed using the test P2096-DOWN STREAM FUEL TRIM LEAN BANK 1.

WHEN MONITORED
With the engine running in closed loop mode, the ambient/battery temperature above (-7° C) 20° F and altitude below 8500 ft.

SET CONDITION
If the PCM multiplies short term compensation by long term adaptive as well as a purge fuel multiplier and the result is below a certain value for 30 seconds over two trips, a freeze frame is stored, the MIL illuminates and a trouble code is stored. Two Trip Fault. Three good trips to turn off the MIL.

POSSIBLE CAUSES
- Good trip equal to zero
- Exhaust leak
- Engine mechanical problem
- O2 sensor
- O2 signal circuit
- O2 return circuit
- Fuel contamination