Uploaded September 2025 | Updated September 2026, 1 hour ago
Here's Why You DON'T COMPRESSION TEST A Cold Engine!! 2 Ways To Do A COMPRESSION TEST On Your Engine!! How To Know If Your Compression Test Results Are Good Or Bad!! #compressionTest #mechanic #automobile
*** I am an Amazon associate. I make a commission based on sales through my Amazon associate links.***
Here's the compression tester tool I used in this video: amzn.to/3I90HX3
***This channel is for entertainment purposes only! Do not do what I do. Do not take my advice. I am not a professional. The methods I use may be completely wrong and/or dangerous. Please seek professional help with anything and everything and do your own due diligence (research). Working on cars is extremely dangerous. I am not responsible for any loss of life or limb or property. DO YOUR OWN RESEARCH. THIS CHANNEL IS FOR ENTERTAINMENT PURPOSES ONLY!***
FTC Disclaimer: I am an Amazon associate. As such, I earn a percentage of sales made through Amazon associate links found in the description of my videos and on my website and other places.
In this video I perform a compression test on my 2005 GMC Envoy. This test was performed on the GM 4.2L, inline six cylinder, Vortec engine. The engine was completely cold during this test. My understanding is that an engine should be warm for a compression test to allow the metal piston rings to expand against the cylinder walls as well as allow the oil to circulate and become thinner thereby providing a better seal. With a warm (not hot) engine you should be able to achieve more accurate results. I explain in this video that my engine was completely cold for the test. This was due to the vehicle being parked for some time as I made other repairs. Interestingly, I also show how much compression can be gained from adding a little oil to the top of the piston (which adds to the sealing ability of the piston rings). This gained compression tells us that perhaps the piston rings themselves are a bit worn. Although, in my case, with a completely cold engine, the numbers may be a bit unclear.
00:00 Introduction
00:35 The Spark Plugs
04:06 Compression Test
07:40 Wet Compression Test
10:49 Conclusion
Here's Why You DON'T COMPRESSION TEST A Cold Engine!! 2 Ways To Do A COMPRESSION TEST On Your Engine!! How To Know If Your Compression Test Results Are Good Or Bad!! #compressionTest #mechanic #automobile
*** I am an Amazon associate. I make a commission based on sales through my Amazon associate links.***
Here's the compression tester tool I used in this video: amzn.to/3I90HX3
***This channel is for entertainment purposes only! Do not do what I do. Do not take my advice. I am not a professional. The methods I use may be completely wrong and/or dangerous. Please seek professional help with anything and everything and do your own due diligence (research). Working on cars is extremely dangerous. I am not responsible for any loss of life or limb or property. DO YOUR OWN RESEARCH. THIS CHANNEL IS FOR ENTERTAINMENT PURPOSES ONLY!***
FTC Disclaimer: I am an Amazon associate. As such, I earn a percentage of sales made through Amazon associate links found in the description of my videos and on my website and other places.
In this video I perform a compression test on my 2005 GMC Envoy. This test was performed on the GM 4.2L, inline six cylinder, Vortec engine. The engine was completely cold during this test. My understanding is that an engine should be warm for a compression test to allow the metal piston rings to expand against the cylinder walls as well as allow the oil to circulate and become thinner thereby providing a better seal. With a warm (not hot) engine you should be able to achieve more accurate results. I explain in this video that my engine was completely cold for the test. This was due to the vehicle being parked for some time as I made other repairs. Interestingly, I also show how much compression can be gained from adding a little oil to the top of the piston (which adds to the sealing ability of the piston rings). This gained compression tells us that perhaps the piston rings themselves are a bit worn. Although, in my case, with a completely cold engine, the numbers may be a bit unclear.
00:00 Introduction
00:35 The Spark Plugs
04:06 Compression Test
07:40 Wet Compression Test
10:49 Conclusion
