High Pressure Fuel System Test: Purpose
WARNING: This page is about a different car, the 2008 Ford Pickup, 2008 Ford F550 Super Duty, 2008 Ford F450 Super Duty, and 2008 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of this test is to determine if the high pressure fuel system is able to reach and maintain the requested desired fuel pressure for a calibrated amount of time. This procedure may be used to assist in diagnosing hard start/no start or driveability concerns.
High Pressure Fuel System Test
NOTE:
Depending on the engine state the fuel rail pressure may vary at idle from 34.47 MPa (5,000 PSI) to 51.71 MPa (7,500 PSI).
- Use the scan tool to carry out the High Pressure Fuel System Test.
- Visually check for engine compartment fuel leaks during this test.
| Commanded Pressure | Measured Pressure | Specification | Measured Variation |
|---|---|---|---|
| 34.47 MPa (5,000 PSI) | +/- 2.0 MPa (+/- 290 PSI) | ||
| 68.95 MPa (10,000 PSI) | +/- 2.0 MPa (+/- 290 PSI) | ||
| 103.42MPa (15,000 PSI) | +/- 3.0 MPa (+/- 435 PSI) | ||
| 137.90 MPa (20,000 PSI) | +/- 3.0 MPa (+/- 435 PSI) | ||
| 169.96 MPa (24,650 PSI) | +/- 3.0 MPa (+/- 435 PSI) |