An engine exhibits a knocking noise. During a cylinder power balance test, the noise abates. Which technician has the correct diagnosis?

Let’s review some of the icons and oddballs we’ve featured here so far.
What does “MIN THK.” really mean?
Don’t waste your time with codebreaking. Just grab a paint pen.
Auto care news and advice you can use.
A helpful video investigation of proper (and improper) torque wrench techniques and habits.
When it is necessary to make your own gaskets, small bolt holes are often the trickiest features to cut.
Featuring state-of-the-art editing, this video is still relevant nearly a century later.
Which of the following is the most critical result of a rust hole in an exhaust system?
Smartphones, laptops, and computers are normally cleared of all data before selling or discarding to protect personal information.
Shop Press is the news and idea hub for everything related to working on cars and trucks, focusing on repair, technology, and wrenching lifestyle. With interesting stories from around the world, features on creative people and solutions, and all kinds of other stuff that’ll make you use your mind and your hands.
Auto care news and advice you can use.
Get up to speed on a safety feature not often seen in the United States.
Do your customers know the benefits of magnetic oil drain plugs? Swap out their standard drain plugs to help protect against unnecessary engine damage.
A customer states the brake pedal falls slightly when the brakes are applied while starting the engine. Which technician response is correct?
In November 1988, two employees snuck a camera into AMC’s Kenosha plant for a farewell tour.
A little glimpse into the world of making old parts new.
Which of the following is LEAST LIKELY to cause an oil leak? Our technicians have the answer.
Spoiler alert: be careful running it through the car wash.
Nick and Lemmy check out a flex plate from an imported Japanese automatic transmission with very few miles under its belt.