2020 Lexus RX450h Smells Like Gas

Identifying Potential Causes of Gas Smells in Your 2020 Lexus RX450h and Essential Safety Measures

Find Repair Location
Reviewed by
Bo Fader
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 2020 Lexus RX450h 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 2020 Lexus RX450h 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.

When the fuel filter begins to clog, the engine suffers from fuel starvation. This will cause a significant reduction in power and may also cause a misfire. These conditions may be intermittent, or constant and worsen over time. As the issue progresses, the engine may being to stall immediately after starting, fail to start, hesitate under throttle, or stall at particular angles on hills.

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 steps should I take to diagnose the gas smell in my 2020 Lexus RX450h?

To effectively diagnose the gas smell in your 2020 Lexus RX450h, start with a systematic approach that prioritizes simpler checks before moving on to more complex diagnostics. Begin by inspecting the area under your vehicle for any visible leaks, as puddles or drips of gasoline can indicate a fuel system issue. Next, ensure that the fuel cap is securely tightened, as a loose or damaged cap can allow gas odors to escape. Following this, examine the fuel lines for any signs of wear or damage, as cracked lines can lead to leaks. Additionally, consider the condition of the fuel injectors, as faulty injectors may also contribute to gas smells; if you suspect an issue, it’s wise to consult a mechanic for a thorough inspection. Don’t overlook the charcoal canister, which plays a crucial role in trapping fuel vapors; a malfunction here can result in noticeable odors. If these steps do not reveal the source of the smell, it’s advisable to seek professional help to ensure a comprehensive diagnosis and resolution of the issue. By following this methodical approach, you can effectively identify and address the gas smell in your vehicle.

What could be causing a gas smell in my 2020 Lexus RX450h?

If you're detecting a gas smell in your 2020 Lexus RX450h, it's crucial to understand the common problems that could be responsible for this alarming issue. One of the primary culprits could be a fuel leak, which may stem from a compromised fuel injector, a damaged fuel line, or even a leaking fuel tank. Additionally, a faulty fuel cap—whether it's loose, cracked, or missing—can allow fuel vapors to escape, leading to noticeable odors inside the vehicle. Another potential source of the gas smell could be an issue with the evaporative emissions system, which is designed to manage fuel vapor release; any malfunction here can result in unpleasant odors. Furthermore, leaks in the exhaust system, such as those from a cracked manifold or a failing catalytic converter, can also allow gas fumes to infiltrate the cabin. Lastly, engine-related problems, including a malfunctioning component or an overly rich fuel mixture, may contribute to the gas smell. Given the safety implications of these issues, it's advisable to have your vehicle inspected by a qualified mechanic to accurately diagnose and address the root cause of the gas odor.

How urgent is it to address a gas smell in a 2020 Lexus RX450h?

Addressing a gas smell in your 2020 Lexus RX450h is not just a matter of convenience; it is a critical safety concern that requires immediate attention. Gas leaks can lead to dangerous situations, including the risk of fire, which can endanger both you and your vehicle. Additionally, inhaling gas fumes poses serious health risks, potentially causing symptoms like dizziness and nausea. Ignoring these signs can also result in more extensive damage to your vehicle's fuel system, leading to costly repairs down the line. If you detect a gas smell, it is essential to act quickly. Start by checking for visible leaks around the fuel lines and connections, and ensure that the gas cap is securely fastened. If the smell persists, it is advisable to consult a professional mechanic who can conduct a thorough inspection and address any underlying issues. Prioritizing your safety and the integrity of your vehicle is paramount when dealing with gas-related concerns.

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.