im looking at by passing the ignition switch to the starter and making a hidden push button start and im looking to find that wiring for that..... anyideas?

 

Not sure if the 2000 S4 has the immobilizer if it does you are out of luck

 

Fairly easy to tell if your Audi received a factory immobilizer. Without starting engine, turn ignition on and look at Instrument Cluster to see if the immobilizer symbol is illuminated. If you see the amber "car with a key" symbol then the car is equipped with OE immobilizer.

I wouldn't switch the high current starter wiring directly. If possible, I'd try to find a low current control wire to switch. More research needed and manuals like Bentley have good wiring diagrams.

 

i don't want to get rid of the key all together, just so that the key doesn't start the car but a button

 

it wont be possible since ur imobilizer wont let u do that!!
ive tried installing a turbo timer and i had problems due to the imobilizer!!
good luck!

 

I know people with turbo timers without any issues with the immobilizer