Blown Head Gasket Tests (2004-2006 2.8L Chevrolet Colorado, GMC Canyon)

You can perform one of four different tests to troubleshoot a blown head gasket issue on your 2004-2006 2.8L Chevrolet Colorado or GMC Canyon.

If you suspect a blown head gasket problem, this tutorial explains all four tests step-by-step.

You'll quickly determine if the head gasket has failed and is causing an engine performance or drivability issue on your Chevrolet Colorado or GMC Canyon.

You can find this tutorial in Spanish here: Cómo Probar Un Empaque De Cabeza (2004-2006 2.8L Chevrolet Colorado, GMC Canyon) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 2.8L Chevrolet Colorado: 2004, 2005, 2006.
• 2.8L GMC Canyon: 2004, 2005, 2006.

Symptoms Of A Blown Head Gasket

Generally, you'll see one of the following symptoms when the head gasket has failed:

• The head gasket failure will cause an engine no-start problem.
• The head gasket issue will allow the engine to start and run, but it'll overheat within minutes (and it'll seem that it's overheating for no apparent reason).

If the head gasket failure still allows the engine to start and run, you'll see one or more of the following symptoms:

• The engine overheats.
• White smoke is coming out of the tail-pipe, and it smells like anti-freeze being cooked.
• The engine oil is thick and a tan to off-white color (mixed with coolant).
• Cylinder misfire or rough idle.

TEST 1: Oil The Color Of Coffee With Too Much Creamer

The most common blown head gasket test is to check the color and condition of the oil adhering to the engine oil dipstick.

A clear indication of a blown head gasket is seeing the oil mixed with coolant (it'll be a color like coffee with too much creamer).

If the engine oil color and viscosity are normal, you'll go to TEST 2.

These are the test steps:

1. 1

   Open the hood on your Colorado (Canyon).

2. 2

   Pull out the engine's oil dipstick.

3. 3

   Check the color of the oil and how thick it is (its viscosity).

4. 4

   You'll see one of two things:
   
   1.) The oil on the dipstick is a creamy, off-white color and is thick as syrup.
   
   2.) The oil is its normal color and viscosity.

Let's examine your test result:

CASE 1: The engine oil looks like 'coffee with too much creamer'. This confirms that the head gasket is blown.

CASE 2: The color of the engine oil is normal. This is the correct and expected test result.

The next step is to check to see if compression/exhaust gases are leaking into the cooling system. Go to: TEST 2: Exhaust Gases Shooting Out Of The Radiator.