egr valve… is it open when it recirculates exhaust gases back or is that closed??? it has what looks to be a two wire plug/ and a vaccum line going from the EET to the EGR VALVE . what condition opens the valve?..and what closes the valve?? meaning for example…[would constant vaccum to the valve, open or close it?.. would a constant voltage to the eet ,open or close it??]
When the valve is energized, open, exhaust gas is allowed into the intake manifold. This happens only under certain conditions. It NEVER happens at idle and it never happens under strong acceleration. The valve opens only when traveling at part throttle.
An EGR block-off plate is a fairly common part.
Disconnect everything from the valve. Start the engine. There should be no vacuum signal. One of the wires may have voltage on it. Rev the engine to 2000 rpm and hold it there. A vacuum signal should appear on the hose. No change on the wires. They are probably just signal wires, reporting back to the ECM that the valve is working…
so… what would disable the egr? stopping vaccum from the eet to the egr?
i have a free flowing true duel exhaust with x-pipe. and i occationally seem to detect a slight preignition type of symtom going down the road… im just trying to get an understanding of my egr system. thanks