2004RennTechE55

I have tested my cars emissions four times and each time it tells me incomplete on catalyst , oxygen sensor and oxygen sensor heat. I have heard that it might be my battery or maybe the auxiliary battery. If you have any suggestions please let me know.

novae500

Who tuned your car? If your rear 02 sensors are turned off, this will cause the issue you have. Could also be if your rear are extended incorrectly can cause a bad reading

Lelix

Same issue, I have the EC tune.

jcjmw

This^^^^. Its a tune issue. Contact your turner and they should be able to take care of it.

I Like Soup

I contacted my tuner and after an initial response, haven't heard back.

A friend of mine in Austin told me that I could run 89 octane and it could take care of that error long enough for me to get my emissions done. I think I'll give it a shot since I've replaced all four O2 sensors and supposedly my O2 sensors aren't reporting...

aixgelo78

Don't do that! I had the same issue with readiness codes. Talked with my tuner, a new tune was supplied and passed NJ inspection.

novae500

Putting different octane isnt going to help. Its the O2s being turned off and the emissions station not being able to read it in their pre testing.

I Like Soup

I'm thinking the triggering of the check engine light is my first concern with regards to the O2 error.

cij911

Not a very smart friend...and the fact that you accepted the answer is equally concerning...

As others have said, contact your tuner.

lowprofile

Floored fab headers, did you lengthen the harness for the rear O2's? I would double check the lengthened harness.