Car Smells Like Propane: What Can Be the Reason?

Smelling gas from a car is really confusing and concerning when you really don’t know the exact cause. It minimizes driver attention and comfortableness when they drive on a long road. It is a basic symptom of engine issues and has an indirect relation with car fuel economy.

Sometimes owners become much worried and confused when they smell propane gas in their car.

Usually, a car produces carbon monoxide gas from its exhaust, and there is less existence of propane in the engine smoke. There are many causes when your car smells like propane, and I have discussed every possible reason with easy solutions.

Main Summary

Some engine components like Faulty or loose gas caps, bad oil filters, faulty oil pan gasket, oil drain plugs, spark plugs, bad oxygen sensors, and nasty exhaust systems are the complete causes of smelling propane gas from your car.

If you have no expertise in vehicle engine function, you must need a mechanic and spend some money to solve this. This article is all about smelling propane gas and a solid step-by-step guide to help the owners.

Car Smells Like Propane: 5 Possible Reasons!

1. Faulty Or Loose Gas Cap

You smell like propane pas in your car, there are many reasons behind it, and sometimes we forget about the most common one. Have you ever looked at your car gas cap closely when you smell like propane in your car?

I know you always close the gas cap tightly though it becomes rusty or scratched after using it for a long time. If you have never looked at it this oil component, your first and foremost duty is to audit the gas or oil cap.

When the gas cap or the fuel tank cap is the main source of smelling propane, swap it as early as possible. It will cost not more than $10 to $20 according to your car model.

2. Bad Oil Filter

When you pour oil or gas into the fuel tank, they don’t go to the engine directly without a purifying process. An oil filter does the work to send pure fuel into the engine and keep your car engine long-lasting.

When the fuel filter fails to perform or has any kind of leaking, it messes up the whole system and sends various problems from propane leaking to milage problems to the owner.

If propane smelling is due to a bad oil filter, clean the filter with a car cleaning kit when you go to test the fuel filter. A quality fuel filter’s price is around $30, and I think exchanging the oil filter is the best option when the oil filter is the main reason for smelling gas like propane.

3. Faulty Oil Pan Gasket And Bad Oil Drain Plug

An oil pan is like a reserve tank and holds engine oil if it is not circulating well. It is situated on the bottom side of the engine, and most of the time, oil leaks from the part. Before going to the oil pan, the oil needs to go with some engine functions that change total fuel formation.

In my sense, oil drain plug or gas cap are closer elements through their working process is quite different. So, it is possible to smell like gas or s propane gas in the car when the car’s oil pan gasket or oil drain plug is corrupted.

The oil drain plug and oil pan are the most crucial parts related to fuel function, and you need to change the whole pan system if something happens in those components. They might cost around $40 combinedly without a mechanic charge if you want to change two items.

4. Spark Plugs And Pressure Regulator Issue 

Spark plugs and pressure regulators might be possible causes if your car smells like gas or propane. I never worked in those crucial components without an auto mechanic’s help. The working process of those components seemed slightly harder to me, and sometimes it varies from vehicle model to model.

Call an expert who has expertise in auto repairing to find out any leaking or smelling issue in those engine items. These are slightly expensive products comparing other engine parts, and you should also spend a large amount of money when you need to change the whole product.   

5. Exhaust And Oxygen Sensor Issue

If you drive your car with a bad oxygen sensor, sometimes it is harmful to vehicle fuel economy and can create a bad smell from your vehicle. The same thing might happen with your car when the exhaust system is older and unhealthy.

Most of the time, a faulty exhaust system creates heavy smoke and a gas smell from the car’s rear side, which is very unhealthy and unethical for your surrounding people.  

Look at the exhaust pipe to see whether the smell is coming from the exhaust system or the oxygen sensor. These are highly mechanical duties and if you don’t have previous experience with those parts, let experts fix them.

Causes of smelling propane in the carSolutionsCosts without mechanic charge
Faulty or loose gas capClose the gas cap tightly or change it$10 to $20
Bad oil filterClean the filter or exchange it$30
Faulty oil pan gasket or oil drain plugSwap them with a newer set$40
Spark plugs and pressure regulator issue Call a mechanic for suitable solutions$30, $25 to $40
Exhaust and oxygen sensor issueLet an automotive expert fix it$100 to $250, $25 to $50

Frequently Asked Questions

1. Is it safe to drive your car if it smells like gas?

Your car is not going to be a blast, and you are quite safe when it smells like little gas. But, someday, you will find other engine problems like poor mileage and black smoke when your car smells like gas. So, fix this issue as early as possible though you are safe, but not your car is.

2. Can bad spark plugs cause a gas smell?

Bad spark has no direct relation with car mileage and gas smelling, as I have said in detail in this article.

But, yes, still, there are chances to smell gas like propane when your car spark plugs have indirect relation with the fuel system. So, fix your car spark plugs before something worse happen and have a smooth ignition and better performance.

3. Can propane fumes from cars harm you?

Usually, a car exits carbon monoxide gas, not propane, from its exhaust pipe. Propane fume is not concerned as a harmful or toxic gas in a general way. But if there is more propane in the air, taking a breath would be slightly tedious to a lack of oxygen.

Final Words

It might increase car lifetime and performance when you don’t ignore anything related to your vehicle. But, when a car smells like propane, leaks oil or has a braking issue, you should not depend on the internet.

You might get some tips or hacks from a car blog, but in real-time, you need an expert to fix an issue that is related to the engine. Buy fuel from a trusted fuel station that might also help you to have fewer gas-smelling issues.

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