Chart A2-5 Fuel Injector Circuit Check For No Start

Diagnostic Chart:

Electrical Schematic:

CIRCUIT DESCRIPTION
The PCM controls each individual injector by providing a ground. This system is referred as Sequential Multiport Fuel Injection (SFI). When the ignition switch is turned to the "ON" or "START" position (engine running), the PCM will energize/de-energize the fuel injector solenoid coil. With this coil energized, a plunger is activated, allowing pressurized fuel to be sprayed through the fuel injectors into the combustion chamber where it is mixed with air from the intake manifold; thus creating the proper air/fuel mixture needed for combustion.

CHART TEST DESCRIPTION
Numbers below refer to circled numbers on the diagnostic chart.
1. This checks for proper fuel pressure.
2. Checks to see if the PCM is controlling the fuel injectors signals.
3. Checks the fuel injector for correct resistance.
4. Checks for voltage at fuel injector.
5. Checks for an open in the ground circuit or a faulty PCM.

DIAGNOSTIC AIDS
There may be fuel spray at the fuel injectors, but it may not be enough to start the engine. If the fuel injectors and their circuit are OK, and fuel spray is detected, the fuel injector nozzle may be partly blocked or restricted. Refer to Chart A2-7A: Fuel System Circuit Opening Relay Check. Chart A2-7A Fuel System Circuit Opening Relay Check

INTERMITTENT MALFUNCTIONS
An intermittent may be caused by a poor connection, rubbed through wire insulation, or a wire broken inside the insulation. Inspect hamess connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals and poor terminal-to-wire connections before component replacement.