2000 A4 1.8T, 127k Manual.

I got the car slightly hit and got it fixed. Car came with aftermarket intake
Everything ran fine, but when i switched back to a stock intake it started idling rough and the car turns off unless i give it gas and keep the idle 2000rpm's or higher for 30 to 40 seconds. After that it runs fine on its own.

This only happens when its cold, If the engine is warm, starts with no problems.