Throttle Opener

Run engine at operating temperature. Ensure idle speed is 650-750 RPM. See CONNECTING TACHOMETER under ENGINE/VIN ID article. Disconnect vacuum hose from throttle opener, and plug hose end. Run engine at 2500 RPM, then release throttle. Compare actual engine speed with specified engine speed. See THROTTLE OPENER SET SPEED SPECIFICATIONS  table. If engine speed is not as specified:

• Replace throttle body.