VDI mod on S4
 

I know this is a redundant topic considering intake swaps . However I decided to share my mod . Instead of using any air pump or the stock(s5) diaphragm for the vdi system. Instead I am using a universal door lock actuator in place of a pump . It is still triggered off an rpm switch , however no airpump or vacuum lines and solenoids. Here it is without being fully mounted . Actuator cost me 4 dollars

should explain that a little further.
Even though it is a "common thing" sometimes it is always better to explain "a better mousetrap"!

Sorry haha , your right . I just meant , if you have a stock air pump with an emission removal , then a pump for emissions modified for less output is overkill . In the same instance replacing a tire pump all the time kind of sucks too . So my idea is an actuator . It has the same idea with less parts and hopefully a better longevity than a tire pump . The idea to make something do less than intended originally for longer than its duty cycle baffles me . So I had this idea. I do have add but hopefully that makes better sense

I think he meant tell us all exactly how to do it.

Lol I'm sorry I thought that was self explanatory . Clearly an actuator no matter what its used for must be mounted otherwise it will just float up and down and be ineffective . So each actuators mounting will be slightly different . A door lock actuator has just the right distance to move for s5 vdi (3/4"-1") . My idea for mounting mine is rods mounted off the original diaphragm . I haven't finished that part yet . However the actuator must be run off an rpm switch . S4s simply have nothing at 5k that turn on that you can use as a switch . So with your rpm switch you will wire the actuator alone instead of the solenoid and a relay . It not only simplifies vacuum routing but wiring as well.

Easiest way to say for me is : replace air pump , solenoid ,and vacuum/ wiring with a door lock actuator . Mounting is different for every actuator.

Where'd you get the door lock actuator?

I can tell you right now that you do not want to do this if you spend very much time in the rpm window that VDI is activated.

Door lock actuators are low duty cycle devices. They are only meant to be activated for a second or less.

Clever idea, but still not a viable solution really.

Got the actuator off eBay . I think the actuator will last as long or longer than the tire pump mod that has the pump continuously running . I do agree that it will fail . However I know tire pumps fail a lot , and I have seen children playing with electric door locks continuously . The battery will usually die or the switch , not the actuators . Time will tell

The tire pump mod didnt work because it isnt supposed to run continuously.

I would have tried an actuator off of a drive by wire car, assuming I could find one that wasn't PWM but rather voltage dependent.

That is a good idea . I'll have to look into VAG products. There are dead Audi's everywhere

The lumbar seat pumps aren't really designed to run continuously in a hot, dusty engine bay either. I've had one on my 6PI for several years and I'm on my second one.

I finally got this running and the actuator does open the vdi , however it does not close it . The polarity has to be reversed , so a double relay needs to be involved