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

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

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Coolant Temperature Switch

Fig. 4 Switches & sensors location. V8 engine:





On V8 engines the coolant switch is located on the front of the intake manifold, Fig. 4. It operates by supplying a signal to the computer when the engine coolant temperature is below 150~ F. This information is required to prevent a change in air fuel ratio until engine operation temperature is reached except there is no control of canister purging.