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Chart A-3 Engine Cranks But Will Not Run:

Engine Cranks But Will Not Run:

CIRCUIT DESCRIPTION
This chart assumes that battery condition and engine cranking speed are OK, and there is adequate fuel in the tank.

CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. A Malfunction Indicator Lamp (MIL) (Service Engine Soon) "ON" is a basic test to determine if there is a 12 volts supply and ignition 12 volts to Powertrain Control Module (PCM). No Data Link Connector (DLC) may be due to a PCM problem and A Charts/Chart A-2 No DLC Data or DTC 12 - MIL "ON" Steady will diagnose the PCM. Chart A-2 No DLC Data or DTC 12 - MIL ON Steady
If Throttle Position (TP) sensor is over 2.5 volts, the engine may be in the clear flood mode which will cause starting problems. The engine will not start without reference pulses and therefore, the Tech 1 scan tool should read RPM (reference) during crank.
2. No spark may be caused by one of several components related to the ignition system. C Charts/Chart C-4B Ignition System Check will address all problems related to the causes of a no spark condition. Chart C-4B Ignition System Check
3. Fuel spray from the injector(s) indicates that fuel is available. However, the engine could be severely flooded due to too much fuel.
4. While cranking engine, there should be no fuel spray with injector disconnected. Replace an injector if it sprays fuel or drips like a leaking water faucet.
5. The fuel pressure will drop after the fuel pump stops running due to a controlled bleed in the fuel system. Use of the fuel pressure gauge will determine if fuel system pressure is enough for engine to start and run.
6. No fuel spray from injector indicates a faulty fuel system or no PCM control of injector.
7. This test will determine if the ignition control module is not generating the reference pulse or if the wiring or PCM are at fault by touching and removing a test light to B+ on CKT 430, a reference pulse should be generated. If injector test light blinks, the PCM and wiring are OK.

DIAGNOSTIC AIDS
^ Water or foreign material can cause a no start during freezing weather.
^ An EGR sticking open can cause a low air/fuel ratio during cranking.
^ Fuel pressure: Low fuel pressure can result in a very lean air/fuel ratio. See Chart A-7 Fuel System Diagnosis under A Charts. Related Tests, Information and Procedures
^ A grounded CKT 423 may cause a "No Start" or a "Start then Stall" condition.