And they said it couldnt be done...

so a VERY reputable shop in MA (where i live/have my car registered) told me that o2 sims, and/or a flash of the obdII would only get rid of dash lights in the event of installing aftermarket headers and deleting the cats. when i go to get my car inspected, i am told i will still not pass emissions. it seems as though the only way to get a passing sticker is to swap back to stock headers before the point of inspection. however, i believe i could install two downstream cats using quick release exhaust clamps, wire the o2 sensors post-cat, and pass inspection. then, once i have my stickers, swap out the cats with straight sections using the same exhaust clamps.

my reason for posting, is to see if anyone can find a problem with this plan. i have searched out the a$$ about headers and cat deletes, and personally think this should work. i am looking for someone to prove me wrong and hopefully save me a headache! if not, then i will end up with a successful setup! Thank you in advance guys, Peace

i passed an obd-II inspection (where they check for error codes, CEL, readiness being set, etc). all i had done was wire in an o2 sim into the ECU compartment. i bought the o2 sim from www.o2sim.com. works perfectly after 7k miles and plenty of mixed driving (300+ mile road trips, around town, etc).

Originally Posted by bryce-o

i passed an obd-II inspection (where they check for error codes, CEL, readiness being set, etc). all i had done was wire in an o2 sim into the ECU compartment. i bought the o2 sim from www.o2sim.com. works perfectly after 7k miles and plenty of mixed driving (300+ mile road trips, around town, etc).

so you mean the o2 sim will be a valid solution given that at least 7k miles are put on the car?

Originally Posted by 330Cole

so you mean the o2 sim will be a valid solution given that at least 7k miles are put on the car?

yes, it worked for me. i have catless headers and i recently passed inspection.


lots of members think you need to go to elaborate lengths to set readiness (i.e. use the innovative LC-1). i passed just fine with the $50 o2 sim. PM me if you have additional questions, i can help you identify the wires that you need to tap into on the ECU harness.

i did it that way, instead of on the actual o2 sensor wires, in case i ever need to change out the o2 sensors. plus, it seems to work better from my experience.