Checking to see if your vehicle has a blown head gasket isn't difficult nor complicated.
In this tutorial, I'll explain the four tests that are done to find out if a blown head gasket issue is causing an engine performance problem. All four tests are explained in a step-by-step manner.
Contents of this tutorial:
You can find this tutorial in Spanish here: Cómo Probar Un Empaque De Cabeza Quemado (1996-2005 3.4L V6 Chevrolet, Pontiac) (at: autotecnico-online.com).
APPLIES TO: This tutorial applies to the following vehicles:
- 3.4L V6 Chevrolet Impala: 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Chevrolet Monte Carlo: 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Chevrolet Lumina Minivan: 1996.
- 3.4L V6 Chevrolet Venture: 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Aztek: 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Grand Am: 1999, 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Montana: 1999, 2000, 2001, 2002, 2003, 2004, 2005.
- 3.4L V6 Pontiac Trans Sport: 1996, 1997, 1998.
Symptoms Of A Blown Head Gasket
It's been my experience over the years having diagnosed many blown head gasket problems, that they usually fall into one of two categories:
- 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 engine in your vehicle starts and runs and the head gasket is blown, 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).
TEST 1: Oil The Color Of Coffee With Too Much Creamer
For our first test we're going to check the color of the engine oil sticking to the engine oil level dipstick.
This is an easy-peasy test and doesn't require any tools whatsoever.
If the oil looks like coffee with too much creamer (a milky white color), then you can conclude that you have a bonafide head gasket failure on your hands.
If the oil has its normal color (usually dark and dirty), then you can move on to the next test.
Let's get started:
Open the hood on your 3.4L V6 Chevrolet (Pontiac).
Pull out the engine's oil dipstick.
Check the color of the oil and how thick it is.
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 one or both of the head gaskets are 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.