Welcome to the Forum! :)
....I'm getting a P1416 DTC code on my 97 vette which I understand to be a problem with the "Secondary Air Injection". I have two questions:
1 - What is the Air Injection?
2 - Is this likely something I can fix / replace myself or will I have to take it to the Dealer? ......
General Operation: Secondary air injection is part of vehicle emissions control. When you first start the car, the Powertrain Control Module (PCM) supplies fuel to the engine in an "Open Loop" mode. "Open Loop" operation creates good cold engine driveability but fuel economy suffers. Once the engine is warm, the PCM switches to "Closed Loop" mode and fuel is supplied at a 14.7:1 air/fuel ratio. The PCM monitors "rich/lean" feedback from the Heated Oxygen Sensors (HO2S) located in the exhaust manifolds/pipes, and depending on the HO2S information, the PCM makes changes to the air/fuel ratio.
Now to your error code: When the car first starts, the PCM supplies fuel somewhat "richer" for improved cold engine driveability(Open Loop Operation). The PCM also commands the Secondary Air Injection pump ON. This fresh air is injected into the exhaust - this extra oxygen introduced into the exhaust system accelerates catalyst operation. The PCM monitors the HO2S sensors during this time to determine if the air injection system is operating properly.
If the PCM detects a problem with the AIR system during Open Loop Operation it runs additional tests of the AIR system during Closed Loop Operation. When a problem is identified a DTC is set.
P1416 is a "Bank 2" fault (passenger side). If there was a driver's side fault. the P1415 would be set. If BOTH banks have problems at the same time, the P0410 would have set. As P1416 only was set, indications are that the problem is not something that effects both banks (sides).
Moisture, water, debris injested into the AIR pump can cause problems.
You might also check pipes/hoses of the AIR system for loose or missing clamps, kinks, holes, pinched hoses, heat damage.
The other checks require the use of a scan tool.
Sorry, not much help.