How to Fix Bad Gas in Your Car: Symptoms and Solutions

Dealing with bad gas in your car is a different beast compared to handling stale fuel in storage. When you’re wondering “How To Fix Bad Gas In My Car”, you’re facing a more complex situation with limited access to the fuel system. Unlike an external tank, you can’t easily drain and clean your car’s gas tank. This means the solutions require a slightly different approach.

Let’s dive into the common scenarios that indicate bad gas in your car and, more importantly, how to address them effectively.

Common Scenarios of Bad Gas & Solutions

When your car is acting up due to bad gas, it usually boils down to the fuel not burning correctly or an interruption in its journey to the engine’s combustion chamber. These are broad symptoms, but they pinpoint the core issue. Here are the most frequent culprits behind bad gas problems:

Phase Separation

Ethanol Defense fuel additive product to prevent phase separation in gasoline.

Phase separation is a known issue with modern ethanol-blended gasoline. If E10 fuel absorbs too much moisture from the air, the ethanol can separate from the gasoline and sink to the bottom of your tank. While phase separation is more common in stored fuel over long periods, it’s less likely to occur spontaneously within your car’s fuel tank because fuel is typically used relatively quickly and the tank isn’t openly vented to the atmosphere.

However, you could introduce phase-separated fuel into your car by filling up at a gas station with compromised fuel. In this case, you’re essentially adding the problem directly to your tank.

Solution: If you suspect phase separation, the best course of action is to have the contaminated fuel professionally pumped out and replaced with fresh gasoline.

Unstable Fuel & Injector Deposits

Bell Injector Cleaner product to remove deposits from fuel injectors and improve engine performance.

Your car’s fuel injectors are critical components that spray fuel into the combustion chamber for burning. Using “less than optimal” fuel, which could be old or degraded, can lead to deposit formation within the injectors. These deposits hinder the injectors’ ability to spray fuel efficiently, impacting your car’s performance. You might notice issues like reduced power, rough idling, or decreased fuel economy.

Solution: To combat injector deposits from unstable fuel, you need to increase the detergency of your fuel. Adding a high-quality, detergent-based fuel additive is the recommended fix. These additives work to clean existing deposits and prevent new ones from forming as you use up the remaining bad gas.

Accidentally Putting Diesel Fuel in Your Gas Tank

Putting diesel fuel into a gasoline car is an unfortunate mistake, but it does happen. This is a serious issue because gasoline engines and diesel engines operate on fundamentally different principles and fuel types. Diesel fuel will not burn correctly in a gasoline engine and can cause significant damage.

Solution: If you realize you’ve put diesel in your gas tank, do not start or drive your car. The safest and most effective solution is to have your car towed to a qualified mechanic. They will need to drain the fuel tank completely, flush the entire fuel system to remove any traces of diesel, and then refill it with fresh gasoline.

Diagnosing Bad Gas in Your Car

Unlike diagnosing bad gas in a storage tank where you can easily take a fuel sample, pinpointing bad gas in your car is more indirect. You can’t readily inspect the fuel. Therefore, diagnosis often relies on observing symptoms and making educated assumptions about the likely cause. Choosing the correct solution hinges on accurately identifying the type of fuel problem you’re dealing with.

What to Do If You Suspect Bad Gas

The appropriate action depends on what type of bad gas situation you suspect:

Diesel in Gas – Immediate Action is Crucial

If you are certain you’ve mistakenly added diesel to your gasoline car, immediate action is necessary. Do not attempt to drive the vehicle. Contact a towing service to transport your car to a reputable mechanic. Avoid relying on anecdotal stories suggesting it might be “fine” to drive. The risk of engine damage and costly repairs is too significant to take that chance. Professional draining and flushing of the fuel system is the only safe solution.

Phase Separation – Proceed with Caution

If you suspect phase-separated fuel, having the tank pumped and refilled is again the best approach. While driving to a mechanic might seem possible, it carries risks. Excessive water content from phase separation could potentially damage your engine. Therefore, towing is still the safer option to eliminate any risk of engine damage during operation with contaminated fuel. However, the repair cost for phase separation is generally less than for diesel contamination, as a full fuel system flush might not be required – just fuel removal and replacement.

Dark Fuel & Injector Issues – Use a Detergent Additive

For issues related to old, dark fuel and injector deposits, a detergent fuel additive is the recommended fix. It’s important to note that fuel stabilizers are preventative measures – they help keep fuel fresh during storage. They won’t reverse fuel degradation that has already occurred. For existing “dark fuel” problems, increased detergency through a fuel additive is the solution to clean injectors and restore performance.

Microbial Contamination – A Deeper Problem

Bellicide biocide product to eliminate microbial contamination in fuel systems.

Microbial contamination represents a more persistent issue. Symptoms can mimic other bad gas problems – a clogged fuel filter and reduced engine performance due to fuel starvation. However, microbial problems are unique because they involve living organisms. Unlike other forms of bad gas, the problem won’t simply resolve itself as you use up the contaminated fuel. Your car’s fuel system has become infected.

Solution: Eliminating microbial contamination requires treating your fuel system with a biocide. A biocide will kill the microbes. Following biocide treatment, it’s essential to replace your fuel filter because it will trap the dead microbial matter. For safe application, it’s recommended to pre-mix the biocide with a small amount of fuel in a separate container before adding it to your car’s gas tank. This method adheres to environmental guidelines and ensures proper treatment.

Check out these related posts:

Ethanol Defense fuel additive product to prevent phase separation in gasoline.

Bell Injector Cleaner product to remove deposits from fuel injectors and improve engine performance.

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