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Posted on October 21, 2025May 21, 2026 by Caitlyn Vance

VGT Turbo Problems and Symptoms: How Variable Geometry Failures Affect Boost, Heat, and Engine Performance

A Variable Geometry Turbocharger (VGT) does more than create boost.

It actively controls airflow, exhaust energy, and turbo speed across different engine conditions.

When a VGT system starts to fail, the issue is not just loss of power – it affects:

Boost Pressure Control
Exhaust Gas Temperature (EGT)
Air-Fuel Ratio
Emissions System Performance

Understanding how a VGT works – and how it fails – is key to diagnosing problems correctly.

Posted on October 17, 2025June 17, 2026 by Caitlyn Vance

Diesel Fuel Algae: What It Is, How to Treat It, and How to Prevent It

If your diesel engine keeps clogging fuel filters, losing power, stalling, or pulling dark sludge from the tank, you may hear someone say you have “diesel algae.”

That term is common, but it is not technically correct.

Diesel fuel algae is usually not algae at all. True algae needs sunlight to grow, and fuel tanks are dark environments. What people call diesel algae is usually microbial contamination made up of bacteria, fungi, yeasts, mold, and biofilm living in the fuel system.

This contamination is often called diesel bug.

The problem starts when water enters the fuel tank. Microbes live in the water and feed on hydrocarbons in the diesel fuel. Over time, they create dark, slimy sludge that can plug filters, restrict fuel flow, damage injectors, corrode tanks, and leave equipment stranded.

Posted on October 14, 2025May 21, 2026 by Caitlyn Vance

Engine Belt Noise and Its Causes: How to Diagnose Squealing, Chirping, and More

If you’re hearing a squeal, chirp, or grinding noise coming from the front of your diesel engine, there’s a good chance the belts – or the components they drive – are involved.

But not all belt noise is actually caused by the belt itself.

The challenge is figuring out:

Or something deeper in the system
Whether it’s the belt
The tension

Posted on September 15, 2025April 30, 2026 by David Ley

Problems with EGR Systems in Diesel Engines

EGR systems are a standard part of modern diesel engines – but they are also one of the most common sources of frustration.

These systems are designed to reduce emissions and meet EPA regulations. However, they also introduce additional components that operate under high heat, pressure, and contamination.

Over time, this combination can lead to performance issues, costly repairs, and system failures.

Posted on September 15, 2025May 22, 2026 by Caitlyn Vance

Why One Diesel Cylinder Runs Hotter Than the Others (And What It Means)

If one cylinder in your diesel engine is running hotter than the others, it’s not random.

It’s a sign of imbalance. In a diesel engine, imbalance means:

Uneven combustion
Uneven load distribution
Increased stress in one area

The important part is understanding why that one cylinder is different.

Posted on September 15, 2025April 30, 2026 by David Ley

Diesel Engine Common Rail Injectors: Potential Failures & Causes

You’ve just been told that you need to replace your diesel engine fuel injectors, but what exactly caused the failure that led to this point?

Posted on September 15, 2025April 30, 2026 by David Ley

What Problems Indicate Head Gasket Failure on C15 ACERT Diesel Engines?

We all know that the head gasket is important. It’s what creates the seal between the engine block and cylinder head to allow for combustion to happen. Without it, your diesel engine won’t run properly.

Posted on September 15, 2025April 30, 2026 by David Ley

When Should You Replace Your CAT C15 ACERT Diesel Engine Turbo?

As you probably know, one of the main differences between the Caterpillar C15 diesel engine and the C15 ACERT is the fact that the ACERT is designed with two turbochargers. That makes this component even more vital to the overall function and health of your diesel engine.

Posted on September 15, 2025April 30, 2026 by David Ley

Why is My Diesel Engine EGR Valve Failing?

Do you know why you need your EGR valve? It’s an important component of your EGR system that takes a ton of abuse because of its environment, and it’s gotten a bad reputation over the years. People often choose to delete it because of the problems it can cause your diesel engine and VGT turbo. But, did you know that this can end up costing you more money in the long run?

Posted on September 15, 2025April 30, 2026 by David Ley

An In-Depth Look at Diesel Engine Common Rail Fuel Injector Problems

If you’re experiencing problems with your common rail fuel injectors, you’ve probably noticed a difference in the way your diesel engine performs. And you’re probably eager to get the issue taken care of.

Posted on September 15, 2025May 21, 2026 by Caitlyn Vance

Converting a Cummins Low-Flow Cooling System to High-Flow: What It Actually Takes

Older Cummins engines – especially Big Cam and NTC/N14-era platforms – used two different cooling system designs:

Low-flow cooling systems
High-flow cooling systems

These systems are not just minor variations.

👉 They are fundamentally different in how coolant moves through the engine.

And that matters when you’re trying to solve overheating – or considering a conversion.

Posted on September 15, 2025July 10, 2026 by David Ley

How to Diagnose Diesel Engine Belt Noise

Diesel engine belt noise is one of the most common drivability complaints on heavy-duty trucks and equipment.

The noise may sound like:

A squeal
A chirp
A screech
A grinding or growling sound

However, the belt itself is not always the actual problem. In many cases, the noise is caused by:

Improper belt tension
Pulley misalignment
Worn bearings
Oil contamination
Failing accessory components

Accurately diagnosing diesel engine belt noise is important because replacing only the belt may not solve the root issue.