Hi guys, newbie here.
Heads up, on my 2006 TJ Sport the MIL lamp came on.
Read the codes and it was P0296, P0298 or close enough. O2 sensors
Bought New "BOSCH" and replaced all 4, after a few miles light came on again.
Read forums, posts and did troubleshooting procedures short of replacing the ECM and the catalytic converters for 8 months and light won't go away. Not only that, new random codes started to show up: P1713, P1776 and P0152.
Note that there was a TSB issued for some of these problems for years 2005 and under I think, but apparently the 2006 ECM had all these mods installed from the factory as the dealer checked my VIN against the TSB's and my car did not need any of those.
The car ran fine or so I though until I went up to Pike's Peak elevation 14,000+ feet were the TJ started coughing and decided to die. After a few attempts the car started again but it ran very rough until we came back down from altitude.
Several months after fuel injector cleaners and so on I found a thread that mentioned that TJ's like the OEM sensors, thought it was crazy but I was out of options at that point (short of a sticker over the MIL lamp).
The Factory brand for the 2006 TJ is NGK as the dealer told me, more specifically is NTK.
NTK is the division of NGK that deals with O2 sensors, NGK deals with spark plugs. Replaced all four sensors (under $200 for all), reset the ECM and never had a problem since. I have driven the TJ for about a 1000 miles and it's good to go.
Here is the link for the literature on the sensors:
Came pretty close of getting rid of the car because the light was pretty frustrating, but it was something as simple as using the right brand which I though was crazy but apparently 2006 TJ and Bosch O2 sensors don't like each other.
Hope it helps!