DELPHI EFI TroublshootingOxygen Sensor (O 2 ) Condition Possible Cause Conclusion Manifold Absolute Pressure Sensor (MAP) A sealed, nonserviceable assembly. A faulty sensor must be replaced. If a blink code indicates a problem with manifold absolute pressure sensor, it can be tested as follows: 1. Make sure all connections are making proper contact and are free of dirt and debris. Remove blower housing. Slide locking tab out and pull off manifold absolute pressure connector. Turn key switch to ON and check with a volt meter by contacting red lead to pin 1 and black lead to pin 2. There should be 5 volts present, indicating ECU and wiring harness are functioning. 2.
Check continuity in wire harness. Ohms between Pin 3 at sensor connector and Black pin 11 connector at ECU should be near zero ohms. If no continuity is measured or very high resistance, replace wire harness. 3. Check to make sure intake manifold is not loose and MAP sensor is not loose. Loose parts would allow a vacuum leak, making MAP sensor report misleading information to ECU. a. Tighten all hardware and perform an ECU Reset and a TPS Learn Procedure to see if MIL will GLVSOD\DIDXOWZLWK0$3VHQVRUDJDLQ,I0,/їQGV a fault with MAP sensor, replace it. 34 KohlerEngines.com 24 690 01 Rev. D Low voltage output. Shorted sensor or sensor circuit. Shorted lead wire. Wiring shorted to ground.
Replace sensor or repair wiring. Contamination of air reference. Remove source of external contamination, protect air reference area. Air leak at sensor or gasket, sensor upper shield damage. Use recommended torque at installation, replace gasket or sensor. Revise application exhaust. Shield sensor from damage. High voltage output. Silica poisoning. Replace sensor. Contaminated gasoline. Use high quality fuel. (QJLQHSUREOHP PLV¿UH &RUUHFWFDXVHRIPLV¿UH Excessive rich air/fuel ratio. Check for high fuel pressure. Leaking injector. Liquid fuel in vent line. Wiring shorted to voltage. Repair wiring. Open circuit, no activity from sensor. Broken element . Sensor dropped.
Hard blow to engine or exhaust system. Defective sensor. Thermal shock. Replace sensor. Slow time response. Open heater circuit. Improper handling. Carbon deposits. Replace sensor. Improper fueling. Correct fueling. Incorrect or contaminated fuel. Use high quality fuel. Excessive engine oil consumption causing exhaust contamination or other exhaust side contamination. Correct engine condition. Heater circuit open/shorted or out of VSHFL¿FDWLRQ Repair short in harness wires, replace sensor.