2021 Lexus RX350 Smells Like Gas

Identifying Potential Causes of Gas Smells in Your 2021 Lexus RX350 and Essential Safety Measures

Find Repair Location
Reviewed by
Devin Cabugcal
Written by RepairPal Car Genius
Updated January 14, 2025
0%
15% chance it's the
Gas Cap
0%
40% chance it's the
Emissions Control System
0%
45% chance it's
Something else
The most common reasons a 2021 Lexus RX350 smells like gas are the gas cap, the fuel system, or the emissions control system.
  • Gas Cap: A loose or damaged gas cap can cause fuel vapors to escape, triggering the check engine light and potentially affecting fuel system pressure.
  • Emissions Control System: A faulty emissions control system can lead to increased hydrocarbon emissions and trigger the check engine light due to malfunctioning components like the EGR valve or O2 sensors.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2021 Lexus RX350 smells like gas?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

A failing catalytic converter can cause a vehicle to fail emissions tests and turn on the check engine light. The exhaust might have an unusual smell. A restricted catalytic converter can result in a loss of engine power.

» LEARN MORE: How to tell if your catalytic converter is failing

The check engine light will illuminate any time there is a failed EVAP system test. This will be indicated by the various on-board diagnostics trouble codes that are stored in the vehicle's memory. Also, in some models, there may be a popping sound accompanying the check engine light, as the leak detection pump continuously attempts to pressurize the fuel tank. The canister may also cause difficulty starting the engine, a rough idle, and poor fuel mileage.

The check engine light will illuminate any time there is a failed EVAP system test. This will be indicated by the various on-board diagnostics trouble codes that are stored in the vehicle's memory. Also, in some models, there may be a popping sound accompanying the check engine light, as the leak detection pump continuously attempts to pressurize the fuel tank. A fuel tank leak may also cause difficulty starting the engine, a rough idle, and poor fuel mileage. When a fuel tank is simply corroded to the point of failure, the exterior tank condition rarely shows damage. The inside of the fuel tank will be rusted or corroded, and rust flakes or other debris may be floating in the fuel.

For most vehicles, the only symptom will be a check engine light or fuel tank filler cap light illuminating on the driver instrument cluster. This is to signal that there is an evaporative emissions (EVAP) leak. In some situations, the vehicle may take longer than normal to start, or, more rarely, the engine may not start at all. on-board diagnostic (OBD) trouble codes will refer to EVAP system failures such as a small or massive EVAP system leak. Lastly, the powertrain control module may notice a lean running condition, which could even lead to random and infrequent misfires.

What are the initial steps to diagnose a gas smell in a 2021 Lexus RX350?

When faced with a gas smell in your 2021 Lexus RX350, it's essential to approach the diagnosis methodically to ensure safety and effectiveness. Start by checking for visible leaks around the vehicle; look for any puddles or wet spots that may indicate a fuel leak. Next, inspect the fuel cap to confirm it is securely tightened, as a loose cap can allow gas vapors to escape. Following this, examine the fuel lines for any signs of wear or damage, as these can be common culprits for gas odors. Additionally, take a closer look at the fuel injector to ensure there are no leaks or malfunctions contributing to the smell. Don’t forget to inspect the fuel tank itself for any cracks or damage that could be releasing fuel vapors. Finally, using a diagnostic scanner can help you identify any error codes related to the fuel system, providing further insight into the issue. By systematically following these steps, you can effectively diagnose the source of the gas smell and take appropriate action.

What could be causing a gas smell in my 2021 Lexus RX350?

If you're detecting a gas smell in your 2021 Lexus RX350, it's crucial to understand the common problems that could be at play. One of the primary culprits could be a fuel leak, which may stem from a damaged fuel line, a faulty fuel injector, or even an issue with the fuel tank itself. Additionally, the evaporative emissions system, designed to manage fuel vapors, might be malfunctioning, leading to the unpleasant odor. A simple yet often overlooked issue could be a loose or damaged fuel cap, which can allow vapors to escape. Furthermore, exhaust system problems, such as leaks or issues with the catalytic converter, can also produce a gas-like smell inside the vehicle. Lastly, engine-related issues, including a rich fuel mixture or malfunctioning sensors, can contribute to the gas odor. Addressing these problems promptly is essential for both safety and vehicle performance, and while some issues may require professional assistance, others can be investigated through careful inspection and basic DIY troubleshooting.

How urgent is it to address a gas smell in a 2021 Lexus RX350?

Addressing a gas smell in your 2021 Lexus RX350 is not just a matter of convenience; it is a pressing safety concern that should be treated with the utmost urgency. The presence of gasoline odors can indicate a fuel leak, which poses a significant risk of fire or explosion if left unchecked. Additionally, inhaling gasoline fumes can lead to serious health issues, including headaches, dizziness, and nausea, particularly with prolonged exposure. Beyond immediate health and safety risks, neglecting this issue can result in further damage to your vehicle, leading to costly repairs down the line. Therefore, it is crucial to take any gas smell seriously and seek professional assistance as soon as possible. Your safety and the integrity of your vehicle depend on your prompt action in addressing this alarming symptom.

You’ve got options with RepairPal

Whether you need a more accurate auto repair estimate or help finding a reputable shop in your area, we’ve got you covered.