1. KCsTJ

    Pre-cats and y-exhaust pipe repair (solved)

    I am troubleshooting a p0431 code on my 05 Sport, "warm-up catalyst efficiency below threshold, bank 2". I have ordered both NTK o2 upstream sensors which may correct the problem. However I plan to also replace the Pre cats as PM cuz it has 101k. I plan to unbolt the 2 pipes connected to the...
  2. KCsTJ

    Engine code P0431

    On day 3 of my new to me 05 Sport with 101k I'm in rush hour traffic, the tj bucks 1x and the CEL comes on. AZ reads the CEL and it shows a P-0431 code which says... "Warm Up Catalyst Efficiency Below Threshold (Bank 2)" There are two catalytic converters coming off the exhaust manifold. My...
  3. T

    Have 04 wrangler 4.0 with P0432 code: can I remove the cats?

    Have 04 wrangler with 4.0, p0432 code, can I remove both pre cats and the main cat with no problem
  4. ARJEEP2006

    What's the difference between a CARB vs. NON CARB compliant cat system?

    What's the difference between a CARB vs. NON CARB compliant catalytic converter system? I have an 06 X with 4.0. I'm considering replacing my cat system with Magaflow system. There are two offerings, part number 93649(non-carb compliant) and 458027 (carb compliant). Does the jeep ECM know if...
  5. Chris

    The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread

    What are Bank 1, Bank 2, etc.? Since this question pops up from time-to-time, here's an easy to follow diagram that illustrates what they mean when your OBDII code scanner (or manual) tells you something like "O2 sensor, Bank 1, Sensor 2": What does upstream and downstream mean? Simple...