andrew lohaus

i'm thinking of creative ways to remove the air pump. i want to reomve both the air pump and the air control valve and use exhaust backpressure to activate the 6 ports and vdi. idealy i'll plumb the exhaust tube from my pre-scilencer back to solenoids and just use the rest of the plumbing and let the ecu open the solenoids at the usual times. i know that the 6 ports and vdi wont open when the engine is not under load as dictated by back-pressure, but i cant figure out if this is a function of the air control valve or if the ecu simply doesn't send the signal to solenoids or some combination of both.


so the question is: does the ecu send the activation signal for the 6 ports/vdi under all conditions (like if i remove the air pump) or does the ecu itself somehow know when the engine is not under load and not send the signal.


i know this is a pretty technical question but someone out there has got to know.

thanks.

Icemark

On the S5 cars, the VDI and aux ports are activated by the S5 ECU, which sends a signal to a electronic pnematic switch that allows the air pump line to feed into the VDI and aux ports.

andrew lohaus

yes yes i know but is the ecu stupid enough to send the signal regardless of engine condition. i want to bypass the air controll valve but dont want to have to buy an aftermarket rpm switch when the ecu already sends a signal under normal driving conditions. baisicaly i want to what, if anything will prevent the ecu from sending it's "open" signal to those solenoids.

HAILERS

It'll never know that the airpump or the acv are removed. Oh, by the way, two seperate signals at seperate rpms. Most of what you want to know is found in the series five fsm at http://www.iluvmyrx7.com, in the Engine Section. Look for the page that is called something like RELATIONSHIP CHART. Frankly nothing is to be gained by removing the airpump. So you have more room with it gone. Just what in the devil do folk do in that big empty space with the airpump gone????. I spend most of my time behind the wheel. The one inside the car

NZConvertible

The ECU operates the 6PI and VDI based on rpm and load (manifold pressure). It has nothing to do with the ACV or air pump.

andrew lohaus

thanks guys. i'm going through this to find an EFFECIENT way to remove the air pump. (i dont see any point in pulling one pump out to put an other (electronic) one in. i'm gona screw around with backpressure (i know thats how the s4 cars do it. if i cant get that to work i'll just leave the thing in. no point in pulling somemthing out unless it genuinly streamlines the opperation of the cars systems.