Liquid Anarchy

iTrader: (2)

Ok, I got to talking about this topic with Bambam7, and he mentioned using the stock hoses, and stock ECU signals to operate the Electric Air Pump, and send the air pressure to the VDI and 6th port actuators. My question is, is there a vacuum diagram in the FSM? I can't find it.

Also, would the best Idea be to just use an accessory 12v source on a relay to turn the pump on? So it's on when the car is on? THX

~Colby

Bambam7

I guess it all depends on how quickly the pump can spool up.
I've heard that someone used a corvette smog pump for their emmisions, but it burnt out faily soon, since it's not designed to be on al the time!
This pump would obviously require you to wire it with a relay to the 3800 rpm signal, so it only turns on when it's needed, BUT if it takes a few seconds to get up to pressure, it's sortof pointless, and it would cause 1st gear performance to suffer. Other gears would be fine though, since revs don't rise as quickly.

As for the diagram... I don't know about the FSM, but there is one in the Chilton and Hayes books.

You shouldn't really need it though, there are only a few lines you need, just follow them.

If the pump is going to be running all the time, all you have to do is to find the hoses that go to the aux solenoid and the VDI solenoid. These will be the ones it needs pressure from. Just hook directly to the air pump.

An idea... you COULD wire the air pump like the fuel pump is wired... with a resistor. Ok, stay with me here:
The pump would be wired with a relay, switched by the key turning on.
But, this circuit would have a good sized resistor inline, dropping voltage to it by about 1/2... This way, the pump is already running at a low speed all the time that the car is on. You could have the 3800 rpm aux solenoid signal hooked to another relay that simply bypasses the resistor when it gets the signal, and the pump would go on full strength.
This way, it wouldn't burn out from being on full power all the time (just like the fuel pump resistor) AND it's spool up time would be greatly shortened.
Man. I might do this myself with the VDI!

Mines RX7

I found your vacuum diagram on page F1-7 of the FSM. That should give you all the info you need.

Bambam
I think your idea would work. It wouldn't be that hard to setup the relay and resistor and such. And they should be available at Radio Shack. You should try it out and tell me if it works becuause I too have been looking for a solution for my VDI and 5th & 6th ports. I would try it, but my car is not running at the moment.

NZConvertible

If you don’t mind spending a little more money on a third rpm switch, you could always have the electric pump turning on before the aux ports solenoid is activated, say 3000rpm. This is below the revs you normally cruise at, so the pump’s on-time would be significantly reduced, and it’s lifespan increased.

Bambam7

That is a definate solution, but RPM switches aren't super cheap, and the beauty of the system with the electric air pump is that you don't need to buy ANY switches, since the ECU already sends signals out at 3800 and 5200 rpms.

It is a simpler solution, but just costs a bit more money.

NZConvertible

Oh OK, I missed the bit about using the ECU to trigger the solenoids. So you just need one rpm switch to trigger the pump. I guess it depends how long that pump lasts running continuously. If it ***** itself every six months, a $50 rpm switch would be a good investment. If it lasts OK, it's not needed. Only one way to find out...

Liquid Anarchy

iTrader: (2)

hmmm

Time to e-mail FC3S.org!

Liquid Anarchy

iTrader: (2)

According to FC3S.org, the air-pump puts out about 40PSI... I'd think it would produce the ~3PSI needed to open the 5/6th port PRETTY quick. I think I'm going to have the 3800 signal open the power-relay; and learn to deal with the .1 second "lag" of the 6th ports opening.



Who'd've thought it? I'll have N/A LAG!