EGR stands for exhaust gas recirculation, and the EGR valve is part of a system that does as the name implies: recirculate exhaust gas back into the engine’s intake manifold for a return trip to the ...

Here's why we need it, how the PCM checks it and why it helps reduce tailpipe gases. Exhaust gas recirculation (EGR) is used to control emissions in every automotive engine built since the Clean Air ...