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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Total Fuel Trim

The value of the Total Fuel Trim is obtained by putting values of Short Term Fuel Trim and Long Term Fuel Trim together. This value indicates how much correction is necessary in order to keep the air/fuel mixture at the stoichiometrical 14.7:1 ratio.