October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.

Trapped Vacuum Spark

Thermal vacuum switch (TVS) is mounted in intake manifold and is used to sense engine coolant temperature. Vacuum check valve is mounted between manifold vacuum, distributor and thermal vacuum switch. System maintains high vacuum levels to distributor during cold engine operation and cold engine acceleration.