Table A1-3 Engine Cranks But Will Not Run

Diagnostic Chart:

Wiring Diagram:

Circuit Description

Before using this table, the battery condition, the engine cranking speed, and the fuel quantity/quality should be checked and verified as being okay.

When the ignition switch is turned to the ON or START positions, the battery voltage is applied to the ignition coil. If the primary coil in the ignition is being toggled to ground through the Ignition Control Module (Igniter), sending a signal to the Powertrain Control Module (PCM), a high voltage is induced in the secondary windings of the ignition coil and is applied through the distributor to the spark plugs.

Diagnostic Aids

^ Water or foreign material can cause a no start during freezing weather. The engine may start after 5 or 6 minutes in a heated shop. The malfunction may not recur until parked overnight in freezing temperatures.

^ Low fuel pressure can result in a very lean air/fuel mixture which may be difficult to ignite.

^ Fouled or damaged spark plugs will cause an Engine Cranks But Will Not Run condition. Refer to Ignition System for spark plug inspection.

^ A vehicle that starts and runs after being brought to the shop for a Engine Cranks But Will Not Run complaint, may have an ignition system that is susceptible to moisture. Spray water on the ignition system components and wiring in order to check for an engine miss or stall.

^ With no MIL and the Engine Cranks But Will Not Run, check for a malfunctioning Main Relay.

^ Check the fuel injector resistor for poor connections or high resistance. Normal fuel injector resistor resistance is 1.9 - 2.8 ohms at 20°C (68°F).

^ Check for a faulty IG fuse.

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

Test Description

The numbers below refer to the step numbers in the Diagnostic Table.

1. The Powertrain OBD System Check prompts the technician to complete some basic checks and stores the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

2. Checks for a spark at the spark plugs.

4. Checks for faulty secondary ignition wires.

7. Checks for proper resistance of the Ignition coil.

20. The test light should flash from dim to bright, indicating a good reference pulse to the ignition control module (Igniter).

21. A test light that stayed ON or OFF in Step 20 indicates an open or a short in the ignition control module (Igniter) trigger circuit.