P0053, now P0171 and P0174

[cashville]

Ok, I just switched the sensors from an H2 that was showing no errors.
I put those sensors, drove for 2 minutes, and the 171 and 174 came up. I erased them, and after a 20min drive they came up again.

So, I'm guessing the new sensors I bought, were reading correctly after all, and there is no problem with them.

I checked for broken bolts on the intakes, but there is none.
I will do a test (cover the exhaust) to check for vacuum leaks, if I don't spot anything, I will switch the MAF from another H2, and check if the errors come up again.

Is there anything you think I'm overlooking, or something?