Hi,
Could someone please tell me what should happen when I unplug:
1. The electrical connector
2. The vacuum hose
From the SAI vacuum control valve? Unplugged both of the above connections
with engine running and there was NO change in engine running. Thanks

 

Nothing that you'll notice. Supplemental Air Injection adds fresh air to the exhaust after it leaves the cylinder. The purpose is to add O2 to that stream so that the un-burned fuel has additional O2 so that - particularly when it hits the cats - it can keep burning to hopefully complete all possible combustion, reducing undesirable exhaust components.
Since this all happens after leaving the cylinder, that system has no effect on the way the engine produces power. It is emissions control only. When you disconnect any of the things you mentioned, you will be degrading the performance of the emissions control system, and will ultimately cause the failure - or worse - of the cats.

 

[QUOTE=H20nSnow;893016]Nothing that you'll notice. Supplemental Air Injection adds fresh air to the exhaust after it leaves the cylinder. The purpose is to add O2 to that stream so that the un-burned fuel has additional O2 so that - particularly when it hits the cats - it can keep burning to hopefully complete all possible combustion, reducing undesirable exhaust components.
Since this all happens after leaving the cylinder, that system has no effect on the way the engine produces power. It is emissions control only. When you disconnect any of the things you mentioned, you will be degrading the performance of the emissions control system, and will ultimately cause the failure - or worse - of the cats.[

Wasn’t going to disable it just wanted to see if it was working. Thanks for the great explanation.

 

SAI is used only at at startup with cold engine. You hear the air turbine making noise to blow fresh air into the exhaust to get the cats heated up faster. After a few minutes the SAI system turns off. When you keep the SAI disconnected you will get a check engine light because the emission control system detects that the SAI does not work.

 

Got it thanks.😊