S/c install, but really poor idle and AFR

Here's the story;

I went to the garage, and got my Alpine s/c stage 0 installed. We ran into some things, the install took about 10 hours (incl. prepping the blower, changing pulley back to 3.50, mounting everthing/rerouting some lines, the support bracket was a pita). I started the engine. That went smooth, on the second turn she started... Sounded great, but only for 10 seconds..

Then, my idle and afr turned crazy.. AFR was @ 19.5 with 800rpm. She wobbled (sounded) extreme lean and like it was an 1960 diesel truck. We found a nipple on the cooling core, and attached it to the FRP. Didn't fix a thing.

As far as i know, there aren't any VAC leaks. All hoses are attached.
- The brake booster is correct, the other nipple goes to the boost actuator
- The FRP goes to the manifold
- Air intake temperature sensor replaced to intakepiping (INJEN)
- Some sort of actuator/canister with sensor underneath the TB is installed (Car-canister-intake/TB), like stock)
- Running a EVAC stage 1 (front), rear valve cover is connected to the intakepiping

What could this be? A problem with that canister, the hoses attached on the wrong side? Is it a fuel pressure problem? TPS sensor connected wrong?
Something else could cause this kind of problem? Were to look...

Thnx guys!