I am in the process of putting back on my air pump and my acv for smog.

When putting in the ACV, I noticed that there is no check valve (the circular spoky bicycle wheel looking thing) If I just install the ACV w/o the check valve, will I still be able to pass smog. What will be the down side of this?

BTW, 87 gxl. All stock.

Tim

 

anyone?

 

I don't know. Never tried that. And for obvious reasons. Go get one.

I'm not sure what happens. That passage leads to the exaust ports. It seems the check valve is there to prevent exaust gasses from coming back towards the air control valve/air pump area. But if the airpump is a pumpin, I'd think that pressure would be higher than the exaust gas pressure. Heck. Give it a try. It seems to me as long as the airpump is pumpin, there won't be a big problem.

Aw heck. Go buy the checkvalve. It can't cost squat.

 

yep, what HAILERS says

I don't think it would be a big problem if you don't have the check valve in there.

If it is a problem, you may want to look real hard at how the ACV functions (with FSM), block the exhaust port, and plumb it (ie apply vacuum to the proper nipples or energize the proper solenoids) so that air is always dumped into the split air pipe, that is, the cat. You may also want to remove the split air solenoid thingy on the ACV to allow for even more split air.

Note: never tried the above but it looks like it would ease the emissions passing process.

Hugues -

 

Mazda put it there for a reason. Its in the FSM's so id say put it in there to be safe.

 

thanks guys, i just got one from the j-yard today. Also got the gasket and the hose connecting the airpump and the acv.

The j-yard guy just let me have it for free.

Tim

 

That's good. You might consider placing that checkvalve in some cleaner and carefully wipe the excess carbon off it. You noticed how its just a piece of nylon??? that moves toward the engine when the pressure is higher in the avc side of the manifold and if the pressure is higher in the intake...the flap shuts off the backwards flow of air from the exaust. It helps if its clean. Just rambling.

 

From what I've heard, you get a big noisy exhaust leak if you don't install the check valve.