Will putting a T on the hose from the airpump and splitting the air into the ACV as well as directly into the cat yield less hydrocarbons on an emissions test?
opposed to having the air pump connected straight to the Cat

 

Neither way will do anything extra for you. It's just something desperate people try to get their car to pass. At low load, under 3500 RPM, the air from the pump is primarily delivered to the exhaust ports, and a small amount is directed to the main cat. Under the conditions of the emissions test, ALL of the air from the pump is already going into the exhaust stream. Running a line directly to the main cat will not get any more air into the system.

 

maybe my original post wasn't clear, sorry.

I am currently one of those desperate people trying to pass inspection. I currently have the electric air pump hooked directly to my cat and am still not passing, would i have greater chances of passing if i split the air from the pump between the cat and acv?

 

Is this electric air pump in addition to the stock air pump, or in place of it? If it's the only pump on the car, directing flow to the ACV would likely give the same result, unless the exhaust ports are the better location to dump the air in (which is your question). Mazda did design the system to pump the vast majority of the air into the ports, while only a little bit went directly to the cat. The increased time the oxygen spends in the exhaust stream & the high EGTs near the ports may have an effect on the chemical reactions that reduce HC & CO levels. This is all speculation of course, but it wouldn't hurt to try.

 

yes, it is in place of my stock pump

 

Then if the Acv is still in proper working condition just run the air pump to that and hook the cat pipe back to the acv like the stock system was set up. And hopefully you are going to a pass or don't pay and see of that works. And make sure the electric pump is working properly...

 

i know this sounds weird but is your tps in spec? my tps was wayy out of whack and i failed the emissions miserably, fixed the tps and it passed with flying colors.


just found the papers for it.... i got 416 HC ppm at 15 mph(2923rpm) and 494 HC at 25mph(2692 rpm)

also failed the CO% 4.08@15mph(limit of .85!! LOL) and 4.82@25mph(limit of 1.23)

i fixed the TPS and i got 17 HCppm@15 mph and 22 HC@25mph
and i went 0.00 CO% all the way across.

so take that into consideration.

 

what did you do to fix the tps? replace it or adjust it somehow?

 

Ok, now im struggling figuring out how to hook everything up with the ACV. Heres what i got so far, and i hope someone can confirm this and fill in the gaps please.

I will hook the air pump up to the outlet on the ACV that goes out to the right (when looking straight into the engine bay) and the outlet on the bottom left of the ACV will run a hose to the Cat correct?
Then there is 3 spots for vacuum hoses, one is hooked up to my BPS the other two are currently vacant from what i've read they go to the Relief solenoid valve and and the Switching solenoid valve on the other end of the engine bay.

What i'm not sure of is which goes to which and where exactly is the connection for those solenoids?

Lastly, if only for the brief moments to pass inspection, do i need to run those vacuum lines to the solenoids or can i just cap them with some electric tape?

 

i had my friend help me out with a homemade 2 light tps adjustment tool. if you cant adjust it right then it could be broken, i was lucky that the PO before me just didnt have any idea how to set it and it wasnt broken.

and for the vacc hoses i really dont have any idea, im pretty sure there are diagrams around somewhere but im lost when it comes to that

 

What series / model of car? The ACV will be different. NAs will have the split air tube connect to a large nipple on the back of the LIM. Turbos will have it come directly off the ACV itself. The switching and relief solenoids and valves can be jury rigged to constantly direct flow to the exhaust ports & cat, but I'll need to know it's his is a turbo or NA. One uses vacuum to activate & the other uses pressure.

 

its an S5 jdm 13bt swapped into an S5 N.A

 

The split air outlet will be next to the ACV (not on like my previous post said); it's an identical looking opening to the coolant port right next to it. There's normally a metal hardline & check valve that head towards the cat.

S5 FSM page F2-57 shows how it works.

The Relief Valve normally uses air pressure to close off, so that means the default is open. Cap/ignore this nipple since it's already keeping the air where you want it, or hook it into an air pump source through the Relief Solenoid.

The Switching Valve & Solenoid use vacuum to switch between the split air path and the port air path. Hook these to a vacuum source, and you're set.