do i have to have either one of these pieces or can i just bolt up the cattback and go? will it mess with the ecu? it doesnt bother me either way...let me know what you guys think...sorry forgot to add test pipe and cattback

 

The 02 sensor is not in the catback.

 

^^^^

 

If you don't mind driving around with the CEL light on then you don't need it. However its not a good idea because then you wouldn't know if you were really having engine problems and would also fail inspections.
The anti-fouler is cheap and easy to install so I don't understand why you wouldn't do it.

 

totally agree^^ thanks for the info..

 

I had to open the hole up a little bit because it was throwing O2 sensor codes, the pcm was thinking the O2 was being lazy. Haven't had a problem since.

 

The anti-fouler wouldn't work for me, I had to get a simulator from www.o2simulator.com and that worked perfect for me.

 

The fouler works perfect for me.

 

where can we buy the cheapest one at??

 

Anti-fouler worked with my catless TBE on my '05 for 2 years, not one CEL. I just bought a cheap one from ebay for like $8.

 

Same here - no problems for little over 1 year now.

 

1 sparkplug antifouler in the test pipe worked for me.