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Can You Drive A Car With A Bad Catalytic Converter? Or Is It Not Safe?

Maintenance and repair of your vehicle can be expensive, and some repairs are critical to keep your vehicle driving safely.

Other repairs are important to keep your vehicle running smoothly and efficiently.

So how does a faulty catalytic converter factor into your vehicle maintenance?

First, let’s review how a catalytic converter works.

It’s a component in your car removes the hydrocarbons, carbon monoxide and other toxic chemicals from your exhaust emissions.

If you notice engine misfires, loss of power and unsightly fuel vapors, chances are you’re having problems with your catalytic converter.

It’s not cheap to replace the catalytic converter, with prices ranging up to $2,000.

Because it can be expensive to replace, you may be wondering if it’s safe to drive with a bad one.

Will you cause more damage by ignoring it?

Let’s review some of your options and the answers to those questions. 

While safety may not be the issue when driving with a bad catalytic converter, it’s definitely recommended that you deal with the problem.

You can still drive your vehicle if the catalytic converter is clogged, but that comes with a price. 

You’ll experience a decrease in your car’s performance, maybe even difficulty getting it to run at all.

When you notice signs of a faulty catalytic converter, it’s time to plan on replacing it as soon as possible.

catalytic converter
image by: Ernesto Andrade/Flickr, CC2.0

Signs you have a problem

If you notice a strong smell, maybe some smoke or fuel vapor coming from your car, chances are the inner lining of your catalytic converter has deteriorated, burning through engine oil that’s causing the foul smell and smoke.

While some may last a decade or more, the signs of a problem are symptoms that your catalytic converter is overheated, clogged or physically damaged.

The causes range from using leaded gas, engine coolant leaking into the combustion system or a bad cylinder head gasket.

When any of these things happen, your clogged converter can have difficulty passing these exhaust gases through your vehicle.

When your vehicle’s engine doesn’t get the air it needs, it becomes sluggish and could suffer more severe consequences down the line.

Some vehicle computer systems register a code that your mechanic can use to identify the problem of a faulty catalytic converter.

The oxygen sensors in your vehicle will produce a corresponding voltage that fits those charges triggered by the problem.

Those sensors evaluate the performance of your catalytic converter and give your mechanic insight into the problem.

Look for “service engine soon” alerts on your vehicle’s dash, usually signaled before you actually begin experiencing a loss of power from your engine.

Failure to act could cause your catalytic converter to collapse and choke your vehicle’s performance, affecting the life of your engine.

What are your options? 

Some vehicle owners think they can avoid problems with the catalytic converter by removing it. 

If you drive your vehicle without a catalytic converter, then get ready for the loud roaring or rumbling sounds when you start your engine.

And this only gets louder and worse when you accelerate.

Without a catalytic converter, your exhaust isn’t working properly, and your vehicle will drive rougher than it normally does.  

You may also notice sputtering as you change your driving speed.

But it’s not a good idea to avoid the problem by removing the catalytic converter.

If your car comes equipped with one, it’s necessary to keep it running smoothly.

If you remove it, it will impact the computer attached to your engine that helps keep your car running well.

In some cases, you may think simple repairs will do the trick.

But there are limited options available for repair.  

A clogged catalytic converter likely will have to be replaced to ensure your car’s engine continues to run optimally.

Your mechanic can evaluate the situation and determine whether it’s best to just replace the catalytic converter.

Replacement also is likely if your catalytic converter has loose parts.

A gentle knock of the component can reveal whether you hear loose parts jostling around.

That’s another time when you need a professional to evaluate the state of your converter.

If you don’t act, you may find your vehicle stopping while driving because your exhaust pipe is completely clogged.

You’ll also need to replace the catalytic converter if it is clogged because of internal oil consumption.

This blockage comes after oil is allowed to enter the cylinders and is left to burn inside the hot catalytic converter.

While you’ll have to make sure you get that oil leak fixed as soon as possible, you’ll also want to replace the impacted catalytic converter to ensure your vehicle operates efficiently and smoothly.

The costs of replacing 

No one likes expensive repairs to their vehicle.

But it’s part of the price of owning machinery.

Things happen and you have to pay for necessary repairs.

The same is true when it comes time to replace a catalytic converter.

It depends on the year, make and model of your vehicle, but expect the cost to replace your catalytic converter to range on average anywhere from $1,000 to $2,500.

That estimate includes both parts and labor, but it’s a necessary expense that’s important to maintain the life of your vehicle.

The cost of parts and labor also include other important tasks that you are responsible for paying for when you seek the repair at your local mechanic’s shop.

Remember, the mechanic will have to diagnose the existing problem and any contributing factors that may have caused it.

There are computer codes to monitor, diagnostic tests to run and other evaluations of your vehicle’s exhaust system and engine components to complete.

This is why it’s so important to trust this type of repair to your favorite mechanic, who can expertly identify with the right diagnostic tools what’s happening with your vehicle.

Some of the damage caused by a faulty catalytic converter may also include issues with your muffler, a few of your oxygen sensors and even your tailpipe – all components of your exhaust system that can become part of the repair of your catalytic converter.

Your mechanic can provide you with a complete explanation, including an estimate for repairs, after the diagnostic work is completed. 

How long can you drive with a bad catalytic converter?

If you’re strapped for cash and don’t really have the funds to replace the catalytic converter right now, then you might be wondering just how long you can ride this one out.

The truth that you may be able to drive it forever, assuming that the catalytic converter is only partially clogged.

But if it’s more than partially clogged, then you really should not be driving with it and get it replaced immediately.