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Express Car Care of Denver

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6 Car Smells That You Should Never Ignore

May 7, 2020 by Denver Express Car Care

Have you noticed your car smells? What is it?

No matter how many times you clean out your car, sometimes things get trapped in the back. Especially if you have kids. A pb&j falls between the seats. Old gym socks are waded up and thrown in the corner. Until eventually, you can’t help but pull everything out of your vehicle to find the culprit.

What we’re talking about here is more than a moldy snack or old gym socks. It’s that smell that lingers when you turn the car on. It’s very distinct. In your gut, you know something is wrong.

Luckily, different parts of your car produce different smells when something goes wrong. If you learn to troubleshoot them early, it can save you by avoiding higher ticketed repair bills, and reducing the risk of being stranded on the road.

Ask yourself these questions.

Is it safe to drive a car that smells like rotten eggs?

6 Car Smells That You Should Never IgnoreThis is the one smell you might mistake for an old, moldy snack left under the seats. As your car operates, you notice a rotten egg smell coming through the vents.

A smell of rotten eggs in your car is from a compound called hydrogen sulfide. This comes from the small amount of sulfate they mix into the fuel you use for your car. If your car is working correctly, sulfur is converted to sulfur dioxide, which doesn’t have an odor. When a part on your fuel system breaks down, the sulfur isn’t transformed correctly, and it can release a rotten egg smell into your car. It’s a malfunction somewhere in your fuel system.

It might be the catalytic converter. It might be a bad fuel filter. It could even be a fuel pressure sensor that causes the system not to work. But when sulfur gas leaks out from the system, you’ll know it. And it won’t go away without repair.

In fact, it can be downright dangerous. This is a problem with your fuel system. That means this is one repair job you can’t put off.

What if my car smells like gas?

Every time you fill up your car with gas, the scent of fuel may linger for a bit. You’re surrounded by it while you get in and out of your car to fill up.

But if you notice it long after you drive away, pay attention. Did you spill some on your hands or clothes while maneuvering the nozzle? Did you step in it and now have it on your shoes? Cleaning it up should solve the problem.

But if it doesn’t, it may be a bigger problem. It might be a problem with your gas cap or a leak in your fuel line. Not only will either of these hurt your vehicle’s fuel efficiency, but they can also lead to dangerous situations. Being that close to fuel vapors can also impact your health.

If the scent won’t go away, it’s time to bring it in and have your car checked.

Why does it smell sugary sweet inside my car?

Your engine coolant is treated with an ethylene glycol, which gives off a sickly sweet smell. You’ll most likely smell it after the engine has warmed a bit, or when your car shuts down.

This toxic fluid is usually a green or orange color when it’s healthy and freshly installed, but will turn a rusty color as it wears down. This tells you the rust inhibitor has been broken down and it’s no longer providing rust control and scale buildup inside your vehicle. If you see drips or a puddle underneath your vehicle in this color combination, it’s time to check for a coolant leak.

This also means it’s starting to impact various parts in your car. It could be coming from a radiator hose, a failed intake manifold gasket, or a bad cylinder head. It might be coming from a leaky radiator cap, or a problem with the radiator itself.

Pay attention to where the smell is worse; inside or outside of your car. If it’s stronger inside, it may be a bad heater core.

Why can I smell exhaust fumes inside my car?

Exhaust fumes have a distinctive odor. You’ve probably noticed it if you walk by a running car, or leave your car in the driveway to warm up on a cold winter day.

You may smell it as you enter your car and prepare to drive away. But if you continue to smell it inside your car, you should never ignore it. Exhaust fumes inside the car most often indicate a problem in your car’s exhaust system. You might also have a problem with the seals on your windows or doors.

This can lead to a dangerous situation. Exhaust fumes contain carbon monoxide, which can be deadly to humans and animals. If you smell exhaust, unroll your windows to let fresh air in, and bring it into our service station as quickly as possible.

What creates a burning smell, almost like burnt carpet?

This is another distinctive smell you’ll notice right away. Because we live here in the Rockies, and free time often means heading into the hills for a day of fun, we tend to wear brake pads differently than other cities across America.

If you’ve been using your brake pads a lot, or pressing down hard because of sporadic traffic, you may notice a burnt carpet smell. This is a sign your brakes are overheated.

While this may be somewhat normal as you’re moving down the mountain pass, back into the city, it’s also a warning. It’s telling you that too much pressure is being placed on the pads; downshift to control your speed instead.

If you smell this on your normal commute here on most flat Denver roads, it’s telling you something else is wrong. You might have a brake problem caused by a seized brake caliper piston. Or maybe you forgot to release the handbrake. This can be checked with a glance.

What is that smell?

While we’ve mentioned some of the more popular smells your car will make when it’s trying to tell you there’s a problem, this by no means is all. Every part operates in its own way. Every problem can create its own unique set of circumstances.

That’s why it’s a good idea to really get to know your car.

If you pay attention to what it looks like, how it drives, and the various smells when it’s operating correctly, you’ll be able to notice quickly when something no longer works well.

Have a question? Give us a call. We’re happy to help you get to the bottom of your car smells, and get you back on the road safely and quickly. 

Filed Under: Tips & Tricks Tagged With: Car Smells

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4200 E. Evans Ave. Denver, CO (map)
Phone: (303) 691-2760
Located just southeast of the Colorado Light Rail station

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