Valve cover replacement problems?

[sdgdf]

I have a 1.4T and I recently got a code P0171, it running lean, and I think p1101. I've had this issue come up 2x before years ago and it was always the PCV on the valve cover. Sure enough this time it was hissing from the PCV.

I changed the valve cover myself. Previously it was under warranty and the dealership did it.

So, now that its changed it has codes P0106 and P0300. No more P071 or P1101. Those codes are MAP sensor value incorrect and misfiring. No more hissing from the PCV on the valve cover but I hear some sort of hissing/wirring from further back by the firewall and it changes with RPM.

So, guesses as to what it is? Bad intake manifold?

I also didn't tighten down the valve cover all the way. The spec is 71 inch lbs. I only did 50, as that feels very tight and I didn't want to break anything. Could there be a vacuum leak around the valve cover? Or something else I missed/messed up?

There's also a code for B2AAA which seems to be nonsense?

How bad is replacing the intake manifold? I know I was supposed to check for that little orange valve before doing the valve cover but I didn't.

Edit: also, I unplugged the MAF sensor wire without disconnecting the battery while doing the valve cover. The write-ups I looked at never mentioned doing that, but it helped provide more room. Would that cause these problems?

 

[Chuzz']

The whole reason for having torque specs is so you'll get the most out of your vehicle by using them. I'd say the odds are pretty good that you're hearing a leak from that valve cover that you didn't fully torque. BUT, keep in mind that I'm not an ASE Certified mechanic and don't claim to be.

 

[Maddmatts]

When I replaced my valvecover, I too didn't disconnect the battery and the computer was very upset on the first few startups. It took something like 2 or 3 starts while clearing codes between each to get the engine running smooth again.

I think the ECU was monitoring different sensors for diagnostics and didn't like being disconnected from them.