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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Fuel Pressure Check


1. Unscrew test port cap nut from injection line.
Note: Use caution to catch spilling fuel and to ensure sealing ball does not fall out of cap nut.
2. Install suitable fuel pressure gauge and hose to test port.
3. Start engine and allow to idle, then measure fuel pressure.
4. Fuel pressure should be approximately 48 psi.
5. Disconnect left pressure regulator vacuum hose. Fuel pressure should increase to approximately 55 psi.
If engine cannot be started, remove relay XVII and bridge terminals 30 and 78. Fuel pressure should be approximately 55 psi.
6. If fuel pressure is not within specifications, slowly squeeze fuel return hose with a clamp near fuel sender. If pressure now increases to under 60 psi, check fuel filter and fuel pump and replace as necessary.