fried wires going to air control valve
 

Hi I'm a newbie so first off, I've spent a lot of time reading posts, and I've learned alot here. This forum is filled with a lot of great info and members.
I was trying to find a leak, and while I was looking around under the hood I saw something strange, The wires that are going to what I believe is the ACV are almost completely fried off. The connecters from the harness are fine though. But, there isnt enough wire coming off the ACV to splice them back together. I searched and I found this: AIR CONTROL VALVE - this is on the lower intake manifold, and the air pump feeds air into it. The ACV controls where the air pump's air goes - into the main cat, into the exhaust manifold, or into the silencer that's under the passenger side headlight. The '89-91 NA's have their 6-ports and VDI actuated from air pump pressure, so the ACV is required unless you fab something up. To remove the ACV, pull it off, remove the studs, put in a fresh gasket and a block-off plate. Make sure to cap off the vacuum lines that went to the ACV as well, and secure the wires up that went to it. I have an S4, how important is this? Everything is completely stock. What would cause these wires to short like that? Any help would be appreciated. Thanks alot.

There is a way to wire the aux ports open (Im not sure but somebody has to know). Anyway you don't need the ACV or air pump (you mine as well remove both if your gonna remove the ACV), but I don't know if you can pass emissions without it, as it is for emissions control. If you pour that alcohol shit for improving emissions from any auto store then you might be able to pass, but its hard to say. Good luck man!

EDIT: 400th post wooooooo :whogives: hehe

[QUOTE]Originally posted by SpeedFreak03
[B]There is a way to wire the aux ports open (Im not sure but somebody has to know). Anyway you don't need the ACV or air pump (you mine as well remove both if your gonna remove the ACV), but I don't know if you can pass emissions without it, as it is for emissions control. If you pour that alcohol shit for improving emissions from any auto store then you might be able to pass, but its hard to say. Good luck man!

Thanks speed freak
I don't have to pass emissions so I'm not worried about that. From what I read The ACV doesn't run the ports on a S4, someone correct me if I'm wrong. But I still have the stock exhaust so don't I need to keep the ACV and the air pump because I still have a CAT?

The ACV has nothing to do with your aux ports on your S4 car. Your wires probably fried because of a short somewhere. That AVC routs the secondary air system to its appropriate places. If you plan to keep your car stock, I would recommend replacing that. Most of us have them laying around.

Jarrett

Thanks J-Rat
Is It going to hurt my car in anyway if I drive it until I get a replacement?

The only POTENTIAL (and I stress potential) problem, is it could cause premature failure of your cats. And you wont pass emissions without it.

Ok Thanks alot!! I'm planning on getting a RB Downpipe/presilincer shortly so Im not to worried about the cats. I'm still wondering what would have caused the wires to short out in the first palace though?

if your going to run a dp/mp, get the ACV blockoff and get that thing outta there. No telling what happened. My guess is the shielding of the wires deteriorated (common problem on FCs). Then the bare wire touched metal... BAM! Instant short.

Who sells the block off plate.
Jrat I'm goin catless on my TII so would I just cap off the vac lines and it will have no ill effects like idle,etc?

Mazdatrix sells the blockoff plate. I just cap all the vac lines. I run no ACV now.

This is probably a dumb question but what section on the mazdatrix site can I find the block off plate? I looked but didnt see any.

If the wires are burnt going to the ACV (usually a soleniod failure) it will often take the transister and resistors that control it in the ECU.

If you check inside your ECU you will probably at the very least find a couple of burnt traces and resistors. You will need to fix that, before you replace the ACV (if you don't go the block off plate route.

Mine are burnt aswell. Why do they need to be replaced if it will no longer be used? Who cares if the part of the ECU that controls it is dead, as it will no longe rbe used?

Well I guess if the car still runs OK then you're fine, but I would look into replacing them anyway, what if they control something else (i dont know if they do im just saying)?

ok, say if my aux ports opening from the air pump into the ACV, and a line tapped off of the main hose. and i want to remove the ACV and put in the block-off plate i have, will i still be able to use the current method i am using to open them?

Vanquished........if you have a series four as your profile says, you should be able to remove the acv, airpump and the things should still operate as stock from the factory....as long as you leave that split air pipe connected up. The air pressure comes FROM the catalytic converter to the small pickoff pipe below the mushroom looking checkvalve then to the aux port intake.

The checkvalve in the split air pipe keeps the pressure in the split air pipe and from escaping out towards the intake manifold.

The airpump and acv play NO part in the auxillary ports opening on a SERIES FOUR car.

I know that's what everybody is saying but ...

isn't there a path from air pump (via ACV) to the actuator pressure line ?

so if the air pump is pushing air to the cat, the pressure at the actuators would be sum of pressure coming from cat and air pump.

Not that it matters,
Hugues -

i have no cats or anything, just straight pipe
i'll see if i can find a picture of what i'm getting at.

here it is..
this is the same set-up to mine.

Frankly speaking about that picture.....that won't work with any consistency except maybe in your driveway.

Air WILL go there in your driveway when the rpms are over 3400 to 3600 rpms.

What makes the air dump out that hose. The ground signal to the Relief solenoid is the answer. No ground from the ECU to the relief solenoid equals no air flowing from that dump hose you are connected to. No air flow out that dump equals no air pressure to the auxillary supply line that you have connected up in your picture.

Before anybody jumps my ass on this subject: go buy yourself a couple of LEDS from RadioShack. Install them in your tps check connector and run them to the cabin. Now start the engine. The LED that is going to the socket (LY colored wire) on the tps checkconnector will be lit up , indicating the Relief Solenoid is energized and passing a vacuum to the acv to keep the air from dumping into the silencer.

Now go for and extended drive in all sorts of driving conditions. Everytime you see that LED on as in lit up.....there is NO air duming into that large relief hose at the bottom of the acv. That light will come and go during driving conditions. Its not just at 3400 to 3600 rpm that the light goes out indicating that the dump hose is now getting air pressure. There are numerous times under 3600 rpm when air will be dumped overboard and pressurizing that dump hose.

So, I'm saying that you will have no control over when your auxillary actuators open/shut with that setup.

In my opinion the only right way is to buy a RPM switch from SummitRacing or the equivalant and using it in conjunction with a spare solenoid (like the ones on your rack). That requires a source of air from the airpump or equivalant. The airpump is aleady there. The source of air would be from the hose b/t the airpump and the acv. There is enough air pressure there all the time whether or not the acv is dumping air overboard into the silencer or not. Been there.....done that. It works each and everytime at whatever rpms you select on the RPM switch. Been there...done that.

There are other more cobbled up methods out there than the rpm switch. Heavy emphasis on *cobbled up*.

And Sureshot......that air coming from the acv is anemic unless your in fifth gear when the split air solenoid opens and the air to the splitair pipe increases quite a bit. But the split air solenoid only opens in......fifth gear. Its the backpressure from the catalytic converter that open series four auxillary actuators.

Pictue: https://www.rx7club.com/forum/attach...&postid=708863

Actually that does work Hailers. I ran with a pressure gauge on that line tapped the same way for about 1000 miles to confirm that there would be the correct pressure at the correct times. Then I ran with the aux ports and a pressure gauge connected there for another 1000 miles again confirming that it works.

Since the aux ports work on air pressure, that is the way it should be tested. Not some LED methods that does not accuratly reflect air routing or pressure.

Now there is often about .75 to 1 PSI dumped down the line, but you would need 1.2 psi to even start opening the aux ports, and just over 2 psi to fully open them.

But unless the air pump is moving that fast, and the ACV has switched to dump they do not activate.

It works fine.

Thats a lot to understand in one sitting.. but from what i can understand, you think that method is wrong, and technically should not be working then?
Because i do know for a fact that my ports open fine. Could it be that i still have enough back pressure in my exhaust ?

I just want to know whether i would loose my way to open my aux ports (using the current method) by installing the RB ACV block-off plate.