First, thanks to all the excellent information on this thread! For my '97 LX450 I've done my best to follow all the advice (disassembling and cleaning the upper intake manifold, etc.) and am down to checking individual components. In the FSM, when checking the EGR valve one step is to put a T splice into the hose from the EGR valve to the EGR modulator to connect a vacuum gauge, and then take the hose from "Port R" on the modulator and feed it into the intake manifold. The FSM says that under these conditions, a hot engine, and 2500 RPM, one should see "high vacuum" on the gauge. Under these conditions my gauge says 6.5 in. Hg vacuum and what I would like to know is if that is "high vacuum", or if not do I have a problem with the EGR modulator or valve. Many thanks in advance!
