Does Starting the Car with AC On Consume More Fuel?

3 Answers
ORichard
07/25/25 6:14am
Using the air conditioning while driving does consume more fuel. Here are some explanations regarding fuel consumption with AC on while driving: 1. Reason for Increased Fuel Consumption: High usage rate of the car's air conditioning. To reduce the fuel consumption caused by the car's air conditioning and lower the actual fuel consumption of the vehicle. Setting the car's air conditioning to the lowest temperature. In this case, the AC compressor will keep running, and the blower will remain at a high fan speed, which can actually increase fuel consumption. 2. Ways to Reduce Fuel Consumption: The correct method is to lower the windows immediately after entering a car that has been exposed to the sun. Do not turn on the AC right away; wait for one or two minutes until the temperature inside and outside the car balances. Then, close the windows and turn on the AC, making sure to set the AC circulation to the indoor circulation mode.
Was this review help?
7
2
Share
VonStella
08/11/25 1:01pm
After driving for so many years, I can confidently say that turning on the AC after starting the car does consume more fuel. This is because the car's air conditioning compressor is driven by the engine. Once you press the A/C button, the engine has to output additional power to run it, increasing the load. This is especially noticeable at idle or low speeds. Based on my tests, fuel consumption can increase by 10% to 20%. For example, if the original fuel consumption was 8 liters per 100 kilometers, it might jump to 9.6 liters. On the highway, the impact is smaller but still significant. My suggestion is to open the windows for ventilation for a few minutes when the weather isn't too hot in summer, then close the windows and turn on the AC once the car cools down a bit. This can save fuel. Additionally, regular maintenance of the AC system, such as cleaning the filters, can also improve efficiency.
Was this review help?
1
5
Share
Expand All
StAdrian
09/27/25 5:17am
From a fuel-saving perspective, turning on the AC immediately after starting the car will definitely consume more fuel. I've tested this many times and noticed that once the AC is on, the engine noise increases while power decreases—clear signs of additional load. The principle is that the compressor consumes engine power, directly driving up fuel consumption. If you want to save money, I recommend not rushing to turn on the A/C after starting; wait until the engine stabilizes before activating the AC. Alternatively, set the temperature higher, like 25°C instead of 20°C. Also, using recirculation mode more often can reduce cooling demand and shorten AC operation time. Remember, opening windows is more cost-effective for short trips, while long journeys justify using the AC for comfort.
Was this review help?
7
1
Share
Expand All
More Forum Discussions

How long after the vehicle inspection can it be checked on 12123?

It can be checked on 12123 72 hours after the vehicle inspection. Introduction to vehicle inspection: The traffic police department conducts an annual inspection of the vehicle's condition and performance, also known as the annual inspection. New vehicles are inspected every two years. Contents of the vehicle inspection: Check whether the engine, chassis, body, and auxiliary equipment are clean, complete, and effective, whether the paint surface is uniform and aesthetically pleasing, and whether the main assemblies have been replaced. Verify whether it matches the initial inspection record; Check whether the vehicle's braking performance, steering control, lighting, exhaust, and other safety performance meet the technical requirements for safe operation of motor vehicles; Check whether the vehicle has been modified, remodeled, or transformed, whether the driving license, license plate, and vehicle file records match the current vehicle condition, whether there are any changes, whether approval and modification procedures have been completed, and whether the license plate, driving license, and enlarged license plate markings on the vehicle are damaged, altered, or unclear, and whether they need to be replaced.
8
0
Share

What is the HOLD light?

HOLD light is the gear lock indicator light. When the HOLD light is on, it indicates that the gear is locked in a specific position. When driving uphill or on icy/snowy roads that require low-gear operation, you can activate HOLD to lock the transmission in second gear. The button for this switch is located in the middle of the gear lever. Pressing it again will deactivate the function. Normally, it's not recommended to use this feature as it may harm the transmission. Automatic gear lock is a forced downshift key, used when gears get stuck or during towing. When HOLD is activated, the parking brake system will automatically engage each time the vehicle comes to a complete stop after braking. You'll feel a release of pressure on the brake pedal, at which point you can release the pedal without worrying about the vehicle rolling. Working principle of gear lock indicator light: The transmission control unit uses this sensor to detect the gear selected by the driver and performs corresponding control actions. Relationship between neutral switch and gear position switch: In older vehicles, the P (Park) and N (Neutral) switches were connected in series with the starter motor switch, meaning the engine could only be started in these two positions. In newer vehicles, the control unit identifies the neutral signal first, then decides whether to engage the starter motor.
11
5
Share

What brand is the Rolls-Royce engine?

Rolls-Royce's engine is from the BMW brand. Here is some information about Rolls-Royce: 1. Rolls-Royce is a world-renowned ultra-luxury car manufacturer, founded in the UK by Frederick Henry Royce (Henry Royce) and Charles Stewart Rolls (Charles Rolls). 2. The cars produced by Rolls-Royce are outstanding representatives of top-tier automobiles, renowned globally for their luxury.
1
3
Share

What Causes Engine Shaking When Warm?

Here are the specific reasons for engine shaking during warm idle: 1. Fuel system issues: Typically caused by fuel line blockages leading to poor fuel supply, manifested as engine shaking, unstable idle, or stalling while driving. Fuel pump failure can also cause engine shaking. To diagnose fuel pump problems, disconnect the fuel line and check fuel flow rate and volume. 2. Electrical system issues: Check whether spark plugs are worn, if gaps are uniform, or if gaps have changed. Additionally, malfunctioning distributors can cause engine shaking. 3. Mechanical reasons: Inspect engine operation for abnormal sounds or valve noise. Check belt condition for looseness.
1
3
Share

What Causes Difficulty in Removing the Car Key?

Car key difficulty in removal can be attributed to the following reasons: 1. P gear not properly engaged: When exiting the vehicle, the gear was not shifted to P or the P gear did not fully engage, possibly obstructed by an object, thus failing to trigger the electronic sensor. 2. Steering wheel locked: The steering wheel was not returned to its proper position when parking, causing an abnormal lock. The solution is to insert the key, attempt to turn the steering wheel left and right while twisting the key, which will release the steering wheel lock. 3. Obstruction in the key slot: The solution involves removing the obstruction, starting the car, shifting the gear again to ensure it is fully engaged, after which the key can be removed.
16
1
Share

What are the items for secondary vehicle maintenance?

There are four main items for secondary vehicle maintenance: engine, clutch, tires, and overall vehicle inspection. Below is a detailed introduction to vehicle maintenance: 1. Overview: Vehicle maintenance refers to the preventive work of regularly inspecting, cleaning, replenishing, lubricating, adjusting, or replacing certain parts of the vehicle, also known as vehicle servicing. Currently, vehicle maintenance mainly includes the engine system, transmission system, air conditioning system, cooling system, fuel system, power steering system, etc. 2. Purpose: The goal of vehicle maintenance is to keep the vehicle clean and in good technical condition, eliminate potential hazards, prevent failures, slow down the deterioration process, and extend the service life.
17
4
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.