The customer reported that the engine hunts at idle, fluctuating up and down to approximately 3000rpm constantly. Restarting the engine would temporarily resolve the issue.

The engine exhibited an erratic idle condition, surging repeatedly between idle and 3000rpm. After a restart, the condition would clear temporarily. Fault codes relating to the crankshaft position sensor and injection pump timing reference were present. Communication with the scan tool later became intermittent or unavailable.