Spark Control System: Description: Notes

Jeep vehicles use spark control devices to assist ignition system in controlling exhaust emissions. They are Spark Control Temperature Override (CTO) valve, Non-Linear Vacuum Regulator (NLVR) valve, Forward Delay Valve, Reverse Delay Valve, and on 4-cylinder engines, a Vacuum Spark Control Delay Valve. System application depends upon engine size, emissions category and vehicle model.