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For 1990-2009 cars only

Engine Cranks But Does Not Run EFI

Go to Engine Controls Schematic

Cell 23: Fuel Controls 3 -- Engine Shutoff Solenoid, Fuel Solenoid Driver


Object Number: 380041  Size: FS
Engine Controls Components L57 EFI
Fuel System Description EFI
Cell 23: Engine Data Sensors 1 - ECT, IAT, MAP
Cell 23: Fuel Controls 2 - Fuel Heater, Temp. Sensor, Water in Fuel Sensor
OBD II Symbol Description Notice
Cell 10: Ignition Switch and Fuse Block
Cell 11: INSTR LPS, TRANS, and ENG-I fuses
Handling ESD Sensitive Parts Notice
.

Circuit Description

This table assumes that battery condition and engine cranking speed is OK. The quantity and quality of fuel is OK and glow plug system is operating properly.

Diagnostic Aids

If no trouble is found and the cause of an Engine Cranks But Will Not Run has not been found, check for:

    • Proper cranking speed, 100 RPMs cold - 180 RPMs hot (a scan tool can be used to check cranking speed by pulling the FUEL SOL fuse and monitoring Engine Speed on scan tool while cranking).
    • Water or foreign material in fuel system.
    • Basic engine problem.

If the Crankshaft position sensor and the Optical/Fuel Temperature are disconnected or malfunctioning at the same time, an Engine Cranks But Will Not Run condition will exist.

Test Description

The number(s) below refer to the step number(s) on the Diagnostic Table.

  1. This step checks for proper cranking speed (see Diagnostic Aids).

Step

Action

Value(s)

Yes

No

1

This chart assumes that all basic engine problems have been checked (low compression, damage parts).

Have all basic engine problems been checked?

--

Go to Step 2

Go to Engine Mechanical

2

Check for proper condition of batteries. Refer to Engine Electrical.

Is the condition of batteries OK?

--

Go to Step 3

Go to Step 12

3

Check for adequate fuel in the tank.

Is the fuel at an adequate level?

--

Go to Step 4

Go to Step 12

4

Check the quality of fuel. Refer to Fuel Quality Diagnosis .

Is the fuel quality OK?

--

Go to Step 5

Go to Step 12

5

Check the glow plug system operation. Refer to Glow Plug System Check .

Are the glow plugs operating OK?

--

Go to Step 6

Go to Step 12

6

Check for proper cranking speed. Refer to Engine Electrical.

Is the cranking speed OK?

--

Go to Step 7

Go to Step 12

7

Check for a restriction in the fuel return system. Refer to Fuel Return System Diagnosis .

Does the fuel return system operate properly?

--

Go to Step 8

Go to Step 12

8

  1. Loosen the injector line at the injector.
  2. Crank the engine.
  3. Repeat for the remaining injectors.

Is there fuel at the each injection line?

--

Go to Step 11

Go to Step 9

9

Check for proper operation of engine shutdown solenoid. Refer to Fuel Injection System Diagnosis .

Is the engine shutdown solenoid working properly?

--

Go to Step 13

Go to Step 12

10

Replace the fuel injection pump. Refer to Fuel Injection Pump Replacement .

Is the action complete?

--

Go to Step 13

--

11

The injection system is OK. Refer to Symptoms .

Is the action complete?

--

Fuel System OK

--

12

Make the appropriate repairs.

Is the action complete?

--

Go to Step 13

--

13

Attempt to start the engine.

Does the engine start and continue to run?

--

System OK

Go to Step 2

Engine Cranks But Does Not Run MFI

Go to Engine Controls Schematic

Cell 22: Glowplug Control


Object Number: 379537  Size: FS
Engine Controls Components L57 MFI
Glow Plug System Description MFI
Cell 22: Fuel Controls 1 - Fuel Pump Control
Cell 11: Gauges fuse
Cell 11: INSTR LPS, TRANS, and ENG-I fuses
Cell 14: S110 [L57]
Cell 14: G200
Cell 14: G102 [Diesel L57]
Starting System
Cell 22: Fuel Controls 2 - Fuel Heater, Water Sensor, Cold Advance
.

Circuit Description

This table assumes that battery condition and engine cranking speed is OK, quantity and quality of fuel is OK and glow plug system is operating OK.

Diagnostic Aids

If no trouble is found and the cause of an Engine Cranks But Will Not Run has not been found, check for:

    • Proper cranking speed, 100 RPMs cold - 180 RPMs hot .
    • Water or foreign material in fuel system.
    • Basic engine problem.

Test Description

The number(s) below refer to the step number(s) on the Diagnostic Table.

  1. This step checks for proper cranking speed (see Diagnostic Aids).

Step

Action

Value(s)

Yes

No

1

This chart assumes that all basic engine problems have been checked (low compression, damage parts).

Have all basic engine problems been checked?

--

Go to Step 2

Go to Engine Mechanical

2

Check for proper condition of batteries. Refer to Engine Electrical.

Is the condition of batteries OK?

--

Go to Step 3

Go to Step 12

3

Check for adequate fuel in the tank.

Is the fuel at an adequate level?

--

Go to Step 4

Go to Step 12

4

Check the quality of fuel. Refer to Fuel Quality Diagnosis .

Is the fuel quality OK?

--

Go to Step 5

Go to Step 12

5

Check the glow plug system operation. Refer to Glow Plug System Check .

Are the glow plugs operating OK?

--

Go to Step 6

Go to Step 12

6

Check for proper cranking speed. Refer to Engine Electrical.

Is the cranking speed OK?

--

Go to Step 7

Go to Step 12

7

Check for a restriction in the fuel return system. Refer to Fuel Return System Diagnosis .

Does the fuel return system operate properly?

--

Go to Step 8

Go to Step 12

8

  1. Loosen the injector line at the injector.
  2. Crank the engine.
  3. Repeat for the remaining injectors.

Is there fuel at the each injection line?

--

Go to Step 11

Go to Step 9

9

Check for proper operation of engine shutdown solenoid. Refer to Fuel Injection System Diagnosis .

Is the engine shutdown solenoid working properly?

--

Go to Step 13

Go to Step 12

10

Replace the fuel injection pump. Refer to Fuel Injection Pump Replacement .

Is the action complete?

--

Go to Step 13

--

11

The injection system is OK. Refer to Symptoms .

Is the action complete?

--

Fuel System OK

--

12

Make the appropriate repairs.

Is the action complete?

--

Go to Step 13

--

13

Attempt to start the engine.

Does the engine start and continue to run?

--

System OK

Go to Step 2