Mastering Diagnostics #12: Mechanical Engine-uity

April 18, 2024
In this video, join Brandon Steckler as he leverages the power of the relative compression test to streamline the diagnostic process.

Motor Age Technical Editor, Brandon Steckler is Back again! And this time with his third video in the series of “Learning how to learn.” His approach this time is to create an engine mechanical fault and use the relative compression test to discover which of the six cylinders is faulted.

Once again, the Pico 4-trace labs scope and High current amp probe will be used to capture a relative compression trace. A second channel of the scope will be used to capture an ignition sync waveform from one of the cylinders. This data is acquired using a secondary ignition capacity probe around one of the spark plug cables.

Stick with Brandon as he first studies the vehicle’s configuration, just like he does when he is facing a challenge in the shop. Pay attention as he walks you through (in real-time) the setup and operation of the lab scope. Witness Brandon capture the effect of cylinder compression on the starter motor and how it is reflected in the “Relative Compression” waveform.

After capturing the data from the engine when it is healthy, Brandon removes a spark plug and re-captures the same data. This is what experimentation is all about! This is the stuff Brandon used to get “GOOD”! Grab a chair and watch how easy it is to begin your journey to being a more efficient, knowledgeable, and confident diagnostician.

Due to factors beyond the control of Endeavor Business Media, it cannot guarantee against unauthorized modifications of this information or improper use of this information. Endeavor Business Media assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. Endeavor Business Media recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of Endeavor Business Media, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage, or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not Endeavor Business Media. The tool and/or equipment featured in this video was supplied by the manufacturer and may or may not be retained by the reviewer at no cost.