Engine Controls - Tests W/o Codes: Other Lexus LS II

Engine Does Not Crank

1. Check starter.
2. Check starter relay.

No Initial Combustion

1. Check ECM power source circuit (ignition keyed).
2. Check fuel pump control circuit.

No Complete Combustion

1. Check fuel pump control circuit.

Difficult To Start, Cranks Normal

1. Check starter signal circuit. See DTC P1500 in COMPUTERIZED ENGINE CONTROLS in «SYSTEM/COMPONENT TESTS»(ref-22208) article.
2. Check fuel pump control circuit.
3. Check engine compression.

Difficult To Start When Cold

1. Check starter signal circuit. See DTC P1500 in appropriate COMPUTERIZED ENGINE CONTROLS in «SYSTEM/COMPONENT TESTS»(ref-22208) article.
2. Check fuel pump control circuit.

Difficult To Start When Hot

1. Check starter signal circuit. See DTC P1500 in appropriate COMPUTERIZED ENGINE CONTROLS in «SYSTEM/COMPONENT TESTS»(ref-22208) article.
2. Check fuel pressure control VSV circuit.
3. Check fuel pump control circuit.

High Idle Speed

1. Check A/C signal circuit.
2. Check ECM power source circuit (ignition keyed).

Low Idle Speed

1. Check A/C signal circuit.
2. Check fuel pump control circuit.

Rough Idle

1. Check engine compression.
2. Check fuel pump control circuit.

Surging

1. Check ECM power source circuit (ignition keyed).
2. Check fuel pump control circuit.

Hesitation/Poor Acceleration

1. Check fuel pump control circuit.
2. Check for faulty automatic transmission (electronics).

1. Check fuel pump control circuit.

Engine Stall After Start

1. Check fuel pump control circuit.

Intermittent Simulation

Monitor circuit/component voltage or resistance while using the following procedures to simulate an intermittent fault. If engine is running, check for Diagnostic Trouble Codes (DTCs). Use test results to identify a faulty component or circuit.

1. Lightly vibrate component.
2. Heat component.
3. Wiggle or bend wiring harness.
4. Spray component with water mist.
5. Remove vacuum from component.
6. Apply vacuum to component.