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Home >> Toyota >> 2004 >> Matrix Base, FWD, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 18 (Engine Control System Self-Diagnostics) >> Diagnostic Tests >> DTC P3190: Poor Engine Power, Or DTC P3191: Engine Does Not Start >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
  1. Using Toyota hand-held tester or scan tool, check for any other DTCs. If only DTC P3190 or DTC P3191 exists, go to next step. If other DTCs exists, diagnose and repair those DTCs first and then retest.
  2. Check vehicle for being out of fuel. If vehicle is not out of fuel, go to next step. If vehicle is out of fuel, add fuel.
  3. Ensure engine oil dipstick, oil filler cap, Positive Crankcase Ventilation (PCV) system and all other air induction system components are intact and operating properly. If problem does not exist, go to next step. If problem exists, repair as necessary.
  4. Check for unusual noise or vibration when starting or accelerating the engine. If no unusual noise or vibration exists, go to next step. If unusual noise or vibration exists, repair or replace engine as necessary.
  5. Check fuel pressure. See PRIUS under FUEL PRESSURE under FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - 4-CYLINDER article. Fuel pressure should be 44-50 psi (3.1-3.5 kg/cm2 ) with engine idling and should remain at least 21 psi (1.5 kg/cm2 ) for a minimum of 5 minutes after engine is shut off. If fuel pressure is within specification, go to next step. If fuel pressure is not within specification, repair fuel system as necessary.
  6. Check Mass Airflow (MAF) meter and Engine Coolant Temperature (ECT) sensor. MAF meter may also be referred to as airflow meter. See AIRFLOW METER and ENGINE COOLANT TEMPERATURE SENSOR under ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING - 4-CYLINDER article. If MAF meter and ECT sensor are okay, go to next step. If MAF meter or ECT sensor is defective, replace components as necessary. See AIRFLOW METER or ENGINE COOLANT TEMPERATURE SENSOR under ENGINE SENSORS & SWITCHES in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  7. Remove passenger's side lower engine cover for access to crankshaft position sensor. Crankshaft position sensor is located on front of engine, near crankshaft pulley. See Figure. Disconnect electrical connector at crankshaft position sensor.
  8. Using ohmmeter, check resistance between electrical terminals on crankshaft position sensor. Resistance should be 985-1600 ohms with sensor temperature of 14-122°F (-10-50°C) and 1265-1890 ohms with sensor temperature of 122-212°F (50-100°C). If resistance is within specification, go to next step. If resistance is not within specification, replace crankshaft position sensor. See CRANKSHAFT POSITION SENSOR under IGNITION SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  9. Disconnect electrical connector at camshaft position sensor. Camshaft position sensor is located on end of cylinder head at flywheel end of engine and contains a Black 2-pin electrical connector with Green and Red wires.
  10. Using ohmmeter, check resistance between electrical terminals on camshaft position sensor. Resistance should be 1630-2740 ohms with sensor temperature of 14-122°F (-10-50°C) and 2065-3225 ohms with sensor temperature of 122-212°F (50-100°C). If resistance is within specification, go to next step. If resistance is not within specification, replace camshaft position sensor. Manufacturer states that converter and inverter assembly must be removed for servicing of camshaft position sensor. The converter and inverter assembly are involved with the high-voltage system used on this vehicle and service procedure should only be performed by authorized dealer.
  11. Check throttle control motor. See THROTTLE BODY under IDLE CONTROL SYSTEMS in SYSTEM & COMPONENT TESTING - 4-CYLINDER article. If throttle control motor is okay, go to next step. If throttle control motor is defective, replace throttle body with throttle control motor as an assembly. See THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  12. Check Throttle Position (TP) sensor. See THROTTLE BODY under IDLE CONTROL SYSTEMS in SYSTEM & COMPONENT TESTING - 4-CYLINDER article. If TP sensor is okay, replace ECM. ECM is located behind glove box. See Figure. If TP sensor is defective, replace TP sensor. See THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
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