Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Ignition System: Description and Operation


Digital motor electronics (DME) is used to control engine operation. Using sensor input, it is able to monitor engine speed, load, temperature, and fuel mixture. These inputs are applied to preprogrammed "maps" to determine ignition output characteristics necessary for optimum fuel economy and performance. Timing is then advanced or retarded as necessary to comply with the ignition map.

NOTE: All DME related components are covered under COMPUTERIZED ENGINE CONTROLS.