Turbocharged Engine Must Idle Before Turning Off?


Must turbocharged engine idle before turning off? Many “skilled drivers” will let you reduce the generation of carbon deposits in the engine.Is that correct? Let me show you that after reading it, you can understand what’s going on.

The relationship between idling speed and carbon deposition of the turbocharged engine

First of all, you have to figure out what a turbocharged engine is. It uses exhaust gas to inhale more air to increase engine horsepower.

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rebuild engine with MaXpeedingRods turbo

When the turbocharged engine is running at high speed, it will be hot and the temperature is When the turbocharged engine runs at high speed, it will be hot and very high temperature. At this time, the coolant and oil start to work, and they “do their best” to cool the engine. When you decelerate and prepare to stop the vehicle, the engine speed decrease, as the cooling operation will slow down. However, if the engine’s high temperature has not subsided, it will carbonize the oil remaining in the turbine, thereby forming carbon deposits.

As a result, the “skilled driver” chooses to continue idling, keeping the engine running. And then, the oil and coolant will continue to work before turning off.

turbocharged engine must idle before turning off-carbon deposition

But in fact, strictly speaking, the idling speed of the vehicle leads to the insufficient fuel combustion as while, which will also cause carbon deposition! Moreover, when driving on urban roads, the traffic is different from that on highways, so it is impossible to keep working at high speed all the time.

Therefore, turbocharged engine must idle before turning off? it seems reasonable that increase the idling time to reduce the formation of carbon deposits, but I still do not recommend it.

What happen while carbon deposits on turbocharged engines

What will happen when carbon deposits on engine parts such as cylinder heads, piston tops, valves, and spark plugs? The first point is the performance. The fuel consumption increases, but the output power of the engine decreases. In short, the car is not “full of power” as before.

Secondly, ignition when the vehicle starts, it’s hard to start or it won’t fire at all.

And then carbon deposits will affect auto parts, etc., it slows parts surface dissipates and accelerate the aging and wear.

The last thing is our natural environment. Carbon deposition causes the number of nitrogen oxides in vehicle exhaust emissions and deteriorates the atmospheric environment.

carbon deposition on turbocharged engine

How to remove and reduce carbon deposits in turbine engines

The first part starts with removing carbon deposits:

1. Spray and clean the throttle valve and intake port with carburetor cleaning agent;

2. Use a cleaning agent to “dissolve” the carbon deposits, and then keep the engine working at the high speed to “blow out” the cleaned carbon deposits;

3.Directly use the pressurized equipment to inject the cleaning agent into the engine combustion chamber, and then extract the waste liquid;

4. Clean fuel additives will have a certain inhibitory effect on carbon deposition

5. Drive the car to a professional vehicle maintenance agency for disassembly and cleaning.

The second part is about reducing carbon deposition:

1. Do not deliberately increase the engine speed, and drive smoothly in combination with the actual road conditions;

2. Do not drive at idling speed for a long time;

3. Choose the quality-assured coolant and oil produced by regular manufacturers.

Write at the end: If you are interested in rebuilding your engine, here are so many turbos for you.


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