HA3 - Check System's Ability to Hold Fuel Pressure

- Cycle the key "ON" and "OFF" several times. Note the fuel pressure.

- Visually look for fuel leaking at the injector O-ring, fuel pressure regulator, and the fuel lines to the fuel charging assembly. Service as necessary.

- Does fuel pressure remain at specification for 60 seconds?

Yes -- Verify integrity of air intake, air filter, no vacuum leaks, EGR valve closed. For vehicles with MAP/BARO: Go to HA4. HA4 - Check MAP/BARO Frequency

For all others: Go to HA6. HA6 - Diagnostic Test Mode (DTM): SFI Engines

No -- Refer to Fuel Delivery and Air Induction.