GM 4.2L Index of Articles

How Often Should I Replace The Spark Plugs? (2002-2009 4.2L Chevrolet TrailBlazer)

How Often Should I Replace The Spark Plugs? (2002-2009 4.2L Chevrolet TrailBlazer)

The spark plugs on your 4.2L Chevrolet TrailBlazer or GMC Envoy are designed to last a very long time. But as the engine wears and it accumulates lots of miles, you're going to have to replace them at shorter intervals. Since quite a few...   read more >>

How To Test Engine Compression (2002-2009 4.2L Chevrolet TrailBlazer)

How To Test Engine Compression (2002-2009 4.2L Chevrolet TrailBlazer)

In this tutorial I'm going to show you how to test the engine compression on the 4.2L equipped 2002-2009 Chevrolet TrailBlazer or GMC Envoy. The engine compression test will help you to troubleshoot a hard to diagnose misfire condition and its...   read more >>

How To Test For A Blown Head Gasket (2002-2009 4.2L Chevrolet TrailBlazer)

How To Test For A Blown Head Gasket (2002-2009 4.2L Chevrolet TrailBlazer)

Testing to see if your 4.2L Chevy Trailblazer or 4.2L GMC Envoy has a blown head gasket is not difficult at all. In this tutorial I'm gonna' explain the four most common tests that are done to verify a blown head gasket. Two of the four tests...   read more >>