Mastering P0491 The Definitive Guide to Emissions System Troubleshooting

Cold is a relative term. The engine coolant temperature needs to be under 104F/40C otherwise the SAP pump WILL NOT be commanded on. If you have ... The OBD-II fault code P0491 means that the Secondary Air Injection System is not providing enough airflow into the exhaust system during ... 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? This is a known issue with the 3.0T. It's emissions an emissions issue, no damage to your car will happen while driving with the CEL. 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 ... Here is the schematic for an 03 manual: There should not be a vacuum line running back to the transmission area, if it is open you have a vacuum leak which can ... The car will need to be in closed loop or hot for the 02 sensors to read the air input correctly. 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. engine code P0491 and P0492 problem solved ... I have been able to fix these trouble codes on the secondary air injection system with the help of ... S-Type / S type R Supercharged V8 ( X200 ) - P0491...secondary air pump? - I just scanned my car for a CEL and came up with this code.