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Hop on Down to the Auto Shop Is your car making a rumbling noise? Do you not get enough power when you press on the gas pedal? Then you need to hop — or rather, drive — on down to the auto service shop. It's okay if you do not know what is wrong with your car, because that is the auto mechanic's job to figure out. They can take a look, run a few tests, and figure out what's going on. Then, they'll give you an estimate for the repairs. Your car will feel like a whole new machine once it's all fixed up! Learn more about that process as you read the articles we've curated here.



Understanding And Recognizing Diesel Blowby

Blowby is a common bugbear for diesel engines of all kinds, but it's often a significant concern for owners of both light and heavy-duty diesel trucks. While you've probably heard the term before, you may not be as familiar with what it means or how it can affect your vehicle. However, understanding blowby and recognizing its symptoms is crucial if you plan to keep your truck for the long haul.

Blowby and Leaking Compression – The Same Thing?

All engines need air, fuel, and spark to run, but there's a fourth, somewhat more mysterious ingredient in the combustion recipe: compression. The simplest way to understand compression is to view it as the internal pressure in your engine cylinders. Diesel engines, in particular, rely on high internal pressure to compress the air/fuel mixture and keep it hot.

Maintaining internal pressure requires tight tolerances on the pistons and valves and numerous seals and gaskets. Although it's impossible to seal your cylinders completely, an engine in good condition can get reasonably close. As long as all of your seals are in good shape, the internal pressure in the cylinders should be relatively close to the manufacturer-designed compression ratio.

A compression leak is any condition that allows some of this internal pressure to escape. Blowby is one form of compression leak where gases from the cylinder can escape through the piston rings. This situation causes one or more cylinders in your engine to pressurize your crankcase, resulting in numerous symptoms and reduced internal engine compression.

How Can You Recognize Blowby?

When you have blowby in one or more cylinders, your engine will run at a lower-than-intended compression ratio. As a result, you can expect your engine to run and idle poorly. You may receive one or more misfire codes, but there's a good chance you'll notice something is wrong with your truck without needing a warning light to tell you.

Since blowby pressurizes your crankcase, you may also see smoke escaping from around your oil filler cap. If you think you might have blowby, you can perform an easy parking lot test by removing your oil filler cap and setting it on top of the fill tube. If there's other pressure escaping from the crankcase to move the cover, that's a strong indication that your engine has substantial compression leakage.

Blowby is a severe problem that likely indicates worn piston rings or a potentially more serious internal engine issue. If you notice the symptoms of blowby in your truck, it's a good idea to have a shop perform a compression test as soon as possible. Finding and repairing the problem is necessary to restore your truck's power and avoid making the situation even worse. Contact an auto service for all your diesel repair needs.