Hi I recently purchase my first 7. I ahve a little problem, the prev owner removed all emission. and in the process of doing that, he also removed the BAC and thermalwax. I was wondering does anyone have any idea how to put the BAC back in? I tried looking in the FSM, but I couldnt find any instructions on doing so. Any input woduld help. Thanks!

 

what series car, s4/s5. N/A or TII?

 

BAC should be really easy. Once you find which one you need (see above) get one from the For sale section. Get (or make) a new gasket. It should just be 2 bolts and some hoses to do.

 

btw, you don't really need the coolant hoses on the BAC. bolt it up and plug it in, the connector looks like a fuel injector connector. Get a factory gasket or use RTV, either will work. i presume you are on the stock ECU so you would need to hook the BAC air hose to the main intake hose.

 

if you have a s4 tii is n332, s5tii n370, n/a s4 is n326( according to mazdatrix)

 

also you just need to get the gasket for it, and put it on the uim ( above where the acv would be) connect it and your done.

 

To clarify the prev owner gave me a box filled with the "emission" parts that he took off. So I'm pretty sure I have the stock BAC. I was actually asking HOW to put it back in. I'm pretty mechanicly challenged so I was wondering if there was a write up or something in the fsm about it that I missed.

 

in the fsm it shows on how to test it, but not to put it back on. it shows a picture in there where its suppose to go, so you have an idea where is was. All you need to do is get a gasket for it, put the gasket over the two studs that are on the uim, put the bac on, screw it back on and connect it to the harness.

 

Install the BAC back onto the manifold using a gasket. Then plumb the air line for the BAC into the air inlet duct (black one connecting to the back of the AFM and throttle body). That's basically it. The coolant line is really only there to keep it from freezing up in cold weather.