Month: August 2016

Oxygen Sensor Replacement

Oxygen Sensor Replacement
Oxygen Sensors

What is an oxygen sensor?

  • An oxygen sensor (or lambda sensor) is an electronic sensing device that is placed throughout a vehicles exhaust system to measures the proportion of oxygen (O2) in the gas being analysed. It was developed by Robert Bosch GmbH during the late 1960s under the supervision of Dr. Günter Bauman.

    Inside an O2 Sensor
    Inside an O2 Sensor

Common Symptoms

  • A failed oxygen sensor (O2 or lambda sensor) may cause the vehicle to fail an emissions test. The failed sensor will cause a trouble code to be set and the Check Engine Light to illuminate.
  • Oxygen sensors can fail if they are contaminated with oil, coolant, or silicone. If fluid contamination has caused an oxygen sensor failure, the source of the fluid must be resolved or the new sensor may be ruined.

Common Misdiagnoses

  • There are many things can be traced back to a oxygen sensor trouble code, even if the sensor is working correctly.
  • Simply changing one or all sensors for a oxygen sensor code may not help your issue.
  • Maintenance and tune up issues can cause exhaust gas to read incorrectly causing a diagnostic trouble code (DTC).
  • Exhaust leaks or unmetered air entering the exhaust system.
  • Intake and exhaust leaks can trigger an oxygen sensor trouble code. Repairing the leak will resolve the problem.
  • On vehicles 1996 and newer, using an inexpensive “universal” oxygen sensor will cause problems with the emissions system and is highly discouraged.

    A newer version update of this O2 Sensor is available
    A newer version is available of this O2 Sensor

Charging system testing and alternator replacement

Image result for car alternator system
Charging system issues

Common Symptoms

  • A weak alternator can result in dimming of the dashboard lights and the headlights.
  • A failing alternator can cause problems starting the vehicle and may result in a repeated need to jump start the vehicle.

Common Misdiagnoses

  • If your battery cannot deliver 10 volts or more during a battery load test, the vehicle may continue to experience starting problems if the battery is not replaced.
    Image result for car alternator
    Insisde a car alternator

    Best Practices

    • The entire starting and charging system should be inspected before replacing the alternator to eliminate other problems that may be affecting the alternator’s performance. For instance, a weak battery and/or battery cables will result in a failed alternator test.
    • The alternator belt may be partially or totally removed while replacing the alternator, so if it shows signs of wear, this is a good time to replace it.

      Charging system testing
      Charging system testing

     

Fuel Pump and filter replacement

 

Image result for fuel pump
Fuel pumps

Common Symptoms

  • A failing fuel pump will not create enough pressure in the fuel system, potentially resulting in a loss of engine power or a “no start” condition. You may also have a lean running condition that can set a diagnostic trouble code and turn on the Check Engine Light.
  • Fuel pumps require replacement if they leak or begin making too much noise, which is a sign of malfunction.

    Image result for delco fuel pump unit
    New fuel pumps

Common Misdiagnoses

  • A clogged fuel filter or problems with the electrical system powering the fuel pump can result in symptoms similar to a failed fuel pump. Have the shop verify that the pump is the problem before replacing.
Image result for fuel pump
Fuel pump diagram

Best Practices

  • The fuel filter should always be replaced when replacing the fuel pump.

    Image for car fuel filter
    Fuel filters