P0491 Empower Yourself with the Ultimate Diagnostic Guide

P0491 and P0492 indicate that you have insufficient air injection flow into the exhaust manifolds. The oxygen sensors are looking for a leaner ... Sensor with the hose: https://amzn.to/3UlZBe9 Valve: https://amzn.to/3ViCOjE VW Scan tool: https://amzn.to/49hIRZn Power Probe 3 ... Secondary AIR Diag VW Jetta P0491 part #1 part #2 https://youtu.be/GtQySXD7yPA?si=vWP3gwqqnzGvDV1i more diag tips for this problem before ... The diagram shows the check valve that is installed in the intake has a single vacuum line that runs to the vacuum canister, however the check valve in my car ... The car will need to be in closed loop or hot for the 02 sensors to read the air input correctly. It soon turns out quite obviously to be a disconnected hose. The hose connects the SAI pump outlet to the Combi valve. Below pictures show the problem and ... The secondary air system helps the car start (cold) and only runs for like ninety seconds, this error pops up usually when the AC is running in the car, and ... The secondary air injection system utilizes ambient air, injecting it into the exhaust, thereby diluting the mixture and facilitating lower emissions ... I have the infamous code P0491, and have been troubleshooting the secondary air pump system on my 02 M5. Took the cover off and verified the ... It's not serious. Secondary air injection is used to warm up the catalytic converters during a cold start. You'll have to get it diagnosed to ...