The reason we need your information in your signature is that the QDM failures differ between the L27 that you have and the L67, and because in your future posts, we won't know what you have.
Ignore the 58. All 92'* do that. You know that now.
Plug your IAT sensor back in. It'* in the back of your airbox.
QDMB is either a transmission shifting issue, a boost control issue (which you don't have in an L27), or an EGR issue. EGR issues usually set a different code, so I'd be watching for shift issues if I were you, particularly with OD. Does the TC lock at about 48mph, dropping your rpm'*? Any other shifting issues from 1-2 and 2-3?
Check to see if your knock sensor wire is too close to a spark plug wire. It'* on the back side of the engine on the passenger side. Make sure the wire isn't shorted. Make sure there isn't another mechanical noise that may set it off.
How many of these codes are 'current' and not 'history'? Your mechanic should know. If you want CURRENT codes, scan them yourself with the procedure in Techinfo.
My advice at this point is to connect your IAT sensor, then disconnect the negative battery cable for 20 minutes. After reconnecting, start the car and idle. If the 43 code comes back at idle, you likely have a problem with the sensor or wiring. You should have no knock at idle.