INTRODUCTION
Note. Introduction infromation not available.
Ported EGR Valve
Warm engine to operating temperature. Increase engine speed to 1900 RPM on non-turbo engines or 2600 RPM on turbo engines. EGR valve should open. Disconnect vacuum hose (upper hose on EGR valve with 2 hoses) from EGR valve. Apply vacuum. Engine should idle rough or idle speed should drop.
Warm engine to operating temperature. Disconnect Red-marked hose from modulator valve. Apply vacuum to hose. If engine RPM drops, EGR valve is okay. If engine RPM does not drop, check hoses, connections, and vacuum tank. Information to check vacuum signal to EGR valve is not available.