What the heck does all this boil down to? LOL


P1416 - GM Type Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled
Description

Secondary Air Injection System Conditions
Location Bank 2
Cause

AIR Test 1: ECT input under 239°F, A/F ratio over 13:1, engine runtime over 2 seconds, throttle angle stable engine load under 6 6%, airflow under 26 g/sec, HO2S-11 bias voltage 365-513 mv, then the PCM detected that the HO2S-11 signal was below 400 mv for a set time period based on ECT sensor input during the test Air Test 2: ECT input from 140-239°F, IAT input over 50°F, engine speed over 600 rpm, engine runtime over 200 seconds, engine load under 5.5%, maximum airflow 17 g/sec, then the PCM detected that the HO2S-11 signal was over 222 mv within 1.5 seconds, and that the SHRTFT was under a specified amount during the test period

 

With the A/F control in closed loop, the PCM activated the AIR pump (it normally runs only at startup, for about 3 minutes, to help the cat heat up to operating temp sooner - and during that time period, the A/F control system is in open loop).

Then it looked for lean readings at the pre-cat O2 sensors, and the response of the PCM by raising the short term fuel trims to correct the lean condition, which would indicate the pump is working, and the air being pumped is reaching the exhaust system. It saw the expected lean condition on bank 1, but it did not see the lean condition on bank 2 (passenger side). Could be a problem with a stuck check valve on the passenger side, or a hole in a rubber supply hose (if there is one - I don't know the details of the 2000 AIR plumbing).

 

Thank you!