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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Checking "Cold" Control Pressure

Checking Cold Control Pressure

This test can be performed on a cold engine only.
It must definitely be performed when encountering starting or warm-up problems.




1. Turn selector valve to position 2. Switch the ignition on.

2. Pressure specifications for the given ambient air temperature are shown in the diagram.




3. Excessive deviations from the specified values are caused by a faulty control pressure regulator for warm running compensation which should be replaced in such cases.