A broken clutch, leaking compressor, or coolant getting into the combustion chamber can cause white smoke from the hood when you turn on your car’s AC. Tears of structures or leakage of fluid matter mainly cause this issue, and sometimes a burning smell can come along.
Well, there are more facts and detail that you need to know to figure out the reasons behind the white smoke from the hood.
So, binge on till the end to know all the reasons and causes responsible.

Reasons behind White Smoke from Hood When Ac Is On
Most people think their car is on fire or something at first glance. But in reality, two reasons mainly make your hood smoke when you turn on the AC.
- Broken Compressor Clutch or Compressor
- Leaking of Coolant
Broken Compressor Clutch or Compressor
The compressor is vital for your AC to function properly as it helps the refrigerate to process the heat transfer.
Moreover, the compressor clutch is another part of the compressor that helps transfer power from the engine to the AC compressor with the help of the pulley. Thus, the AC works perfectly in a regulated manner and does not turn on automatically when it’s not needed.

That’s not all; the compressor clutch and compressor thus are necessary components that can create white smoke if broken or torn.
This internal equipment is also affected when the compressor clutch or compressor is broken. Thus, it does not let the AC function properly, which is the main reason behind the white smoke coming from the hood.
There are a few ways to understand if your compressor or compressor clutch went bad:
- If the refrigerant is leaking.
- You are unable to turn on/off the AC
- Weird or loud noise coming from the AC
- The sudden rise in the temperature
Leaking of Coolant
Leaking of coolant is another and most common reason for which white smoke comes from the hood.
When coolant leaks from a damaged seal or gasket and gets in contact with the combustion chamber, it creates smoke under the hood which starts coming out when you turn on the AC.
How to Fix White Smoke from Hood When AC Is On?

If you see white smoke coming from your hood when AC is on, you can do a few things to fix this issue.
Step 1: You first need to check if the smoke is whitish, as most of the time, the color of the exhaust can help you understand the issue better.
Step 2: Make sure to check the warning lights on the dashboard to see if the car is overheating.
Step 3: Open the hood after you have turned the engine off.
Step 4: Call a mechanic or any technician to fix this problem, as that individual will help to restore the leakage or broken clutch.
Step 5: If you fail to call any mechanic and want to take matters into your own hands, you should try to adjust the cap, belt, or clamp if those need to be fixed properly.
Step 6: If the coolant is low in quantity, add more to it.
Step 7: Check the gasket and replace it with a new one if needed.
Why Is the Car Smoking under the Hood but Not Overheating?

You may see white smoke from your car’s hood without the car getting overheated. Except for leaking coolant, there are some other reasons which can cause the smoke:
- Condensation
- Broken filler cup
- Oil leaking
- Burned electrical wires
When these four situations occur, the water under the hood might try off, or the oil or any liquid will contact the engine, which will cause white smoke. Or if the electric wire is burning, the smoke will also be seen from the hood.
Different Exhaust Smoke
Since smoking from the hood when AC is on is our main focus, you should also know different kinds of exhaust smoke, allowing you to understand what’s happening with your car.
Blue or Gray Smoke
It is a sign that your engine is burning and creating smoke. Broken or damaged gaskets/ seals or clogged PVC can also be the reason behind this.
White Smoke
The smoke is mainly seen when your coolant gets in contact with a car engine due to the leakage.
Black Smoke
This smoke occurs when incomplete combustion occurs or your vehicle burns excessively raw fuel.
Bottom Line
By far, you must have understood why white smoke from the hood when AC is on. Smoke coming from the hood is one of the concerning things that car owners go through most of the time. Seeing smoke coming from the hood is scary, but the reasons can be very common sometimes.
Now, you see if your car has any broken or leaked important parts causing the smoke. If that happens, contact a mechanic instead of dealing with your own. Thus, you can have a good car riding experience.
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