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4 Signs Your Car Might be Experiencing Excessive Backpressure

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Excessive backpressure can occur within your vehicle when the exhaust system isn't able to expel of all the waste products created by the engine. That might not sound like a real problem, but it can lead to overheating and other internal failures. Here are just four signs that your vehicle is suffering from excessive backpressure.

1. Decreased Power and Fuel Economy

If your engine can't release all of the pressure that builds up from waste products, it won't be as able to burn new fuel or draw in new oxygen to ensure that fuel burns optimally. This means that excessive backpressure will result in both poor performance and poor fuel economy. If you notice that your vehicle is taking longer to build up speed while also demanding more trips to the gas pump, excess backpressure might be to blame.

2. Your Exhaust is Blocked

If your exhaust system becomes blocked, it naturally won't be able to release the gases produced by the engine. The most common causes are mud and ice, so take a look inside the tail pipe, making sure you turn the vehicle off before you do so, to see if you can spot any blockages. If the vehicle has experienced below-freezing temperatures, try tapping the muffler to see if it sounds hollow. If not, there might just be a hunk of ice inside.

3. Your Catalytic Converter Needs Replacing

When too much backpressure builds up, it's normally down to a faulty catalytic converter. These help turn the hazardous and environmentally-damaging compounds that build up within your engine into more benign gases by the time they exit the exhaust. This is great for improving emissions, but it does mean that there's something of a bottleneck within the system. The symptoms of a faulty converter also include a reduction in performance and efficiency, but you're also likely to experience misfiring. This will in turn cause the converter to overheat, which can melt its components.

4. Your Exhaust System is Too Narrow

Single exhaust systems are fine for traditional four-cylinder engines, but they'll often struggle to expel everything produced by either a turbocharged four-cylinder, six-cylinder, or eight-cylinder; there's just too much fuel being burnt for all waste gases to be expelled without creating too much pressure. Of course, manufacturers know what they're doing, but anyone driving a vehicle with a powerful engine who frequently pushes it to its limits might experience an increase in backpressure.

If these signs have presented themselves, make sure you take your vehicle to a mechanic. They will be able to measure the backpressure with a pressure gauge to see if anything is wrong, then recommend the best way to deal with the problem.