Testing The Oxygen Sensors Ford 1.9L, 2.0L

Symptoms Of A Bad Oxygen Sensor

The effects of a bad oxygen sensor can be very subtle since they usually do not cause serious drive-ability problems. Here are the most common symptoms:

• The check engine light (CEL) will be illuminated on your instrument cluster.
• The diagnostic trouble codes lighting up the CEL usually are:
  • P0131 Upstream Heated Oxygen Sensor (O2S11) Circuit Out Of Range Low Voltage (Bank 1).
  • P0133 Upstream Heated Oxygen Sensor (O2S11) Circuit Slow Response (Bank 1).
• Really bad gas mileage.
• Won't pass state mandated emission testing.

More Test Articles

I've written quite a few 1.9L, 2.0L 'how to' tutorials that may help you troubleshoot the issues on your Ford Escort, Mercury Tracer or Ford Focus. You can find the complete list at:

• Ford 1.9L, 2.0L Index Of Articles.

Here's a sample of the Ford 1.9L, 2.0L articles you'll find:

1. Crankshaft Position (CKP) Sensor Test.
2. How To Test Engine Compression.
3. Ignition Coil Pack Test (this info is found at: easyautodiagnostics.com).