Anti-Afterburn Valve

Fig. 15 Anti-afterburn valve:

1. Disconnect air inlet hose from air cleaner at anti-afterburn valve, Fig. 15.
2. Start engine and run at idle.
3. Block anti-afterburn valve air inlet and ensure engine speed does not change.
4. Increase engine speed and quickly release accelerator, then ensure air is drawn into anti-afterburn valve for a few seconds after releasing accelerator.
5. If air is drawn in for more than three seconds or not drawn in at all replace anti-afterburn valve.