I have JBA longtube headers, off road Mac prochamber crossover, mil delete plug ins and electronic cutouts installed on my 2005 GT. Also have pretty much of the mods that every other new Mustang has including Zex Nitrous that I use very rarely..had a tune done at Brenspeed but now the thing will not pass the emissions here in Illinois. The report says that my O2 sensors are not ready, and the cats aren't ready, do I need to reinstall some cats back on the car or can I get around this somehow? Don't know to much about the pollution crap on the car but I thought that the mil delete plugs would trick the computer into saying things were working properly. Don't really know which way to turn right now except to check the tune to see if they turned off the sensors at Brenspeed, or go and buy a BBK crossover with cats and retro-fit it to fit my longtubes and check the o2 sensors to make sure they are working. I may sound stupid because I am about this exhaust crap...the first time that it has failed.

 

Put the sniffer in someone elses tailpipe and run the test...

 

They didn't use a sniffer they just plug er in and it showed that the car isn't ready...

 

You probably have the rear O2s turned off. Even if you do turn them on, you are probably gonna need some kind of cat to pass legitimately. I dont know how well the MIL eliminators work...

Like sicride, easier to use someone elses car...

 

yeah I know here in AZ, if you dont have cats, you wont pass..but we have one of the more stricter states...

 

Youlr gonna need some cats and make sure you have the o2s turned on to pass.

 

Have you contacted Brenspeed? They should be able to write an emissions-friendly tune.

 

move to another state?

i seriously have no idea though i'm interested in what everyone says here.. i'll be the one lurking in the corner.. ignore me..

 

OP, you need to get your hands on an Actron OBDII reader. Either buy one for $50 or borrow. It will tell you when your car is literally READY to pass emissions. It takes a certain amount of miles and cycles before the car can pass emissions after being flashed or reset in any way.

I'm unsure if a Rear O2 can show READY without cats being present, but my guess is they can.

Here in GA they do a visual inspection for the cats so I had to bolt some in just to pass.


Also, with Brenspeed - they told me the ONLY thing they do for an emission tune is turn the rear O2's on. That's it.

 

I could be mistake, but I don't think you can pass smog with long tube headers because it changes the location of the O2 senors. That is how it is hear in Cali****mefornia.