Unveiling the Secrets of P0491 A Complete Guide to Diagnosis and Repair

Code P0491 Secondary Air Injection System (Right Bank). Subscribe. Feb 3, 2006 | 10:03 PM. It was running like a dream, but recently threw a code. P0491. I checked the code and it's the secondary air Injection. I have had the hardest ... Performed SAI Self Test: Failed. Monitored input and output of secondary air pump. Was able to confirm activation of air pump and adequate flow. Ford Focus P0491 Trouble Code Repair Disclaimer: This video is not meant to be a definitive how to.Always consult a professional repair ... Find out everything about the P0491 fault code In this video, we will explore the description, symptoms, causes, and solutions to resolve ... 2011 458, the CEL came on. I drive back home and hooked up my code reader, it showed a P0491 Secondary air injection system, Bank #1. Anybody have this problem? The air injection pump is failing or the fuse has blown. It's a high-current fuse (40A if I recall). For troubleshooting, I would look from the load side of ... It is a round valve with a small vacuum hose attached at the top rear. Remove the OEM diverter valve, and set it aside. The new parts (Autozone ... P0491 code means there is a problem on the side of the engine which contains cylinder #1 due to a bad air inlet, faulty wires, relay, pump, or fuse. The PCM will set the 0491/0492 codes based on what the O2 sensors see. So if there is a link then perhaps the faulty PCV valve is changing the exhaust mixture.