How to Troubleshoot a Honda Odyssey EGR Valveby Alibaster Smith
The Exhaust Gas Recirculation valve, or EGR valve, system in your Honda Odyssey reduces oxides of nitrogen by recirculating them back into the combustion chambers in your engine. By doing this, the EGR valve can optimize the combustion in the engine to reduce emissions. If the valve is malfunctioning, it can cause the engine valves to knock against the piston heads. In a Honda engine, this can be fatal for the valves because Honda uses a compact engine design, called an interference engine design, which causes the valves and the piston heads to intersect if the timing of the valves and pistons is not correct.
Remove the bolts holding the manifold cover in place on the top of the engine using a socket wrench. Pull the manifold cover off and locate the EGR valve on the right hand side of the engine. The base of the EGR valve is gold in color with a black top, and is about 2.5 inches in diameter.
Start the Odyssey and allow it to reach normal operating temperature.
Pull the hose off from the Odyssey's EGR valve, and attach the hose from the hand vacuum pump to the EGR valve. This valve connects the valve to the engine. By pulling the hose off the valve and hooking up the pump to the valve, you are creating a vacuum leak.
Apply vacuum to the EGR valve. The vacuum should remain steady and the Odyssey should run poorly. If the vacuum doesn't stay steady and the engine doesn't run smoothly, replace the valve. If the vacuum does stay steady and the engine doesn't run poorly, check the intake manifold for any debris or blockage.