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Home >> Volkswagen >> 1987 >> Vanagon Syncro AWD L4-2109cc 2.1L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Component Tests and General Diagnostics >> Fuel Pressure, Checking >> Checking Residual Pressure
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Checking Residual Pressure



Residual pressure, checking

- Shut off engine and wait ten minutes
2.0 to 2.5 bar (29 to 36 psi)

If pressure value NOT obtained there are three possible causes

Caution: Use extreme care not to damage fuel lines when clamping

- Check fuel pump check valve by clamping off line from fuel pump
- Check fuel pressure regulator by clamping oft return line to tank
- Check fuel injectors by clamping off lines from injectors to pressure regulator, if necessary check injectors

In each of these cases, observe gauge pressure while clamping off the individual lines.
If the pressure drop ceases or slows dramatically, the problem is in the indicated component.