2007 BMW 335xi Smells Like Gas

Diagnosing Fuel Smells in Your 2007 BMW 335xi: Common Causes and Solutions for a Safe Drive

Find Repair Location
Reviewed by
Andrew Hajjar
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 2007 BMW 335xi 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 efficiency.
  • 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 2007 BMW 335xi 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 causes of a gas smell in a 2007 BMW 335xi and how to diagnose it?

When dealing with a gas smell in your 2007 BMW 335xi, it's essential to approach the diagnosis methodically, starting with the most straightforward checks before moving on to more complex issues. Begin by inspecting the fuel system for any visible signs of a gasoline leak, as this is a critical safety concern that should be addressed immediately. Look closely at the fuel tank, lines, and injectors for any signs of leakage. If no leaks are found, the next step is to examine the fuel pump and regulator, as problems with these components can also lead to a gas smell. Ensure that the High-Pressure Fuel Pump (HPFP) is properly installed and that all connections are tight, especially if it has been recently replaced. Additionally, check the sealing washers on the spark plugs, as damaged or improperly torqued washers can allow fumes to escape into the intake system. By following this structured diagnostic approach, you can effectively identify the source of the gas smell and take the necessary steps to resolve the issue, ensuring both your safety and the proper functioning of your vehicle.

What are the common causes of a gas smell in a 2007 BMW 335xi?

When you detect a gas smell in your 2007 BMW 335xi, it’s crucial to understand the common problems that could be at play. One of the first areas to check is the gas cap; if it’s loose or damaged, it can allow fuel vapors to escape, leading to a noticeable odor. Additionally, inspect the fuel system components, including the fuel pump, fuel filter, and fuel injectors, as leaks in these areas are frequent culprits. The emissions control system also warrants attention, as any malfunction can contribute to gas smells. Furthermore, be aware that faulty wiring in the fuel pump, particularly in models from 2007 to 2012, may indicate a more serious issue that could require immediate action, especially if it relates to a recall. Given the serious risk of fire associated with gas leaks, it’s advisable to conduct a thorough inspection of the fuel system, including the fuel tank and spark plugs, to ensure your vehicle remains safe and functional. Addressing these issues promptly not only enhances your vehicle's performance but also safeguards your well-being on the road.

How urgent is it to address the gas smell in my 2007 BMW 335xi?

When you detect a gas smell in your 2007 BMW 335xi, it is crucial to act swiftly due to the serious implications of neglecting this issue. Gasoline leaks not only pose a significant fire hazard, endangering your life and the lives of those around you, but they can also lead to harmful health effects from inhaling toxic fumes. Symptoms such as dizziness, headaches, and nausea are common and should not be taken lightly. Furthermore, ignoring the gas smell can result in more severe mechanical problems, which could escalate into costly repairs down the line. Therefore, addressing the gas smell immediately is essential for your safety and the longevity of your vehicle, ensuring that you avoid potential dangers and expensive fixes in the future.

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.