Disable Google Updater Agent from Mac Startup
Disabling the startup item can be done by deleting the file
/Library/LaunchAgents/com.google.keystone.agent.plist or
adding a new "Disabled" property to it (in case you want to keep the file):
<key>Disabled</key>
<true/>
Your plist file should look like this when disabled:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Disabled</key>
<true/>
<key>Label</key>
<string>com.google.keystone.root.agent</string>
<key>LimitLoadToSessionType</key>
<string>Aqua</string>
<key>ProgramArguments</key>
<array>
<string>//Library/Google/GoogleSoftwareUpdate/GoogleSoftwareUpdate.bundle/Contents/Resources/GoogleSoftwareUpdateAgent.app/Contents/MacOS/GoogleSoftwa
reUpdateAgent</string>
<string>-runMode</string>
<string>ifneeded</string>
</array>
<key>RunAtLoad</key>
<true/>
<key>StartInterval</key>
<integer>3523</integer>
<key>StandardErrorPath</key>
<string>/dev/null</string>
<key>StandardOutPath</key>
<string>/dev/null</string>
</dict>
</plist>