Why a diesel engine needs a turbo
Before understanding that the turbo is not working, it is important to understand how it is designed and why it is used in diesel cars at all. The turbo works on the following principle:- the engine's exhaust gases spin the turbine wheel;
- the wheel drives a compressor that forces air into the cylinders;
- thanks to the increased amount of air, more fuel can be supplied - and more power can be obtained.
Without a working turbo, a diesel engine loses its main advantages: torque, efficiency, and stable operation under high loads.
Main signs that the turbo is not working
As soon as the turbo stops functioning, it is almost immediately felt while driving. Here are the key symptoms to pay attention to:1. Loss of power
One of the most common signs is that the car has become slow to accelerate, especially on the highway or when overtaking. This happens because the engine operates without boost - like a naturally aspirated engine.2. Increased fuel consumption
If the turbo is not working on a diesel, the engine starts to consume more fuel. You may notice that the same routes use more diesel, especially during active driving.3. Black or blue smoke
If black smoke pours from the exhaust pipe when you press the gas, this is a sign of a lack of air and an excess of fuel. Blue smoke may mean that the turbo is pushing oil.
Visual and audible signs
Some symptoms can not only be felt but also heard or seen.1. Whistling or howling under the hood
Unusual sounds are a frequent indicator that the turbo is not in order. Whistling may mean there is a leak or mechanical wear.2. Oil leaks on the pipes
If the turbo has stopped working, traces of oil often appear on it. This indicates damage to the seals or axial play.3. Errors on the dashboard
Many diesel cars can diagnose faults themselves. When the turbo fails, the "Check Engine" indicator may light up.
Reasons why the turbo is not working on a diesel
If you notice that the turbo is not working, it is important to understand the reasons. Here are the main ones:Mechanical wear
The turbo is a high-speed unit. Over time, the bearings and blades wear out. This is especially true for cars with mileage over 150,000 km.Lack of oil
The turbo requires constant lubrication. If the oil is of poor quality, contaminated, or insufficient, it leads to overheating and destruction.Ingress of foreign objects
Even a tiny particle of dust can damage the blades. This often happens when the air filter or pipes are damaged.Overheating
If the driver often turns off the engine immediately after active driving, the turbo does not have time to cool down. This reduces its service life.What to do if the turbo has stopped working
If you notice the above symptoms and want to understand whether the turbo is not working on a diesel, act step by step:Step 1: Check visually
- Inspect the turbocharger pipes: check for cracks or traces of oil.
- Check the oil level and quality.
- Listen to the sounds when the engine is running - check for squealing or metallic noise.
Step 2: Perform a simple check
- Stand on a flat road and sharply press the gas.
- If the car accelerates "sluggishly" and smoke comes from the pipe - this is a warning sign.
Step 3: Contact a specialist
- Diagnostics at a service station includes measuring boost pressure, inspecting the turbo, and checking errors with an OBD scanner.
