Talking About Fuel Delivery Systems

When you first purchased your car, you were impressed at how well it accelerated and maintained its speed while driving on the freeway. Now that some time has passed, and you've adjusted to your car's performance, you've noticed that your car's horsepower seems to be steadily declining—even though there aren't any warning lights or strange noises coming from your car. In such a case, one (or both) of these issues may be causing your performance problems.

Exhaust Back Pressure

Just like your respiratory system, your vehicle's air intake and exhaust systems need to breathe. The air that passes through your intake system and into your engine can be thought of as your car's inhale, and the air exiting through your exhaust system and muffler can be thought of as the exhale.

If you've modified your vehicle's muffler or exhaust system, then you haven't only made an audible difference in your car's operation—you've also changed it's breathing cycle. If your muffler or exhaust system modifications aren't suited for your car's breathing cycle, then it causes an issue known as back pressure.

Back pressure is the measurement of resistance your engine encounters when it sends used air and combustion fumes through your exhaust system. If any components in your exhaust system (such as your catalytic converter, exhaust pipe, muffler, or tailpipe) are too restrictive for your vehicle's engine, then the resistance your engine experiences during the exhaust stroke will permanently reduce your horsepower during each piston cycle.

However, back pressure isn't only caused by exhaust modifications. Carbon buildup, poor vehicle design, and catalytic converter issues can also increase your vehicle's back pressure. If your vehicle's back pressure problems are caused by poor vehicle design, then replacing the original parts with aftermarket components that accommodate the breathing cycle of your engine will provide a slight performance increase.

You'll only experience a drastic loss of horsepower if your back pressure is severely restricting your engine's breathing cycle. If you suspect that this issue is causing your performance problems, then have your vehicle's exhaust back pressure measured and repaired by a certified technician.

Dirty Filters

Your vehicle's various systems rely on filters to operate efficiently. Your engine, air intake, fuel, and several other systems can only operate as designed if they're able to remain clear of combustion byproducts and other contaminants—which are typically trapped by their corresponding filters. However, many car owners don't notice when their filters require replacement since they don't cause a noticeable performance problem until they completely fail.

For example, your vehicle's oil filter is tasked with filtering soot and metal particles from the oil that pumps throughout your engine. If the filter becomes clogged with these contaminants, then small amounts of soot and metal will pass through the filter and continue to circulate throughout your engine—where they'll cause permanent damage to the internal components. Similarly, your fuel filter can allow rust and other contaminants to flow through your fuel system and into your engine if it isn't changed periodically.

Each of your vehicle's filters requires replacement at varying intervals. Although you may have heard of a few standard mile markers at which your various filters should be replaced, you should consult your vehicle's owner or service manual to determine the specific interval at which each of your filters require replacement. By replacing your filters in a timely manner, you can not only maintain your vehicle's performance, but increase the lifespan of your vehicle.

Don't settle for a sub-par driving experience. If you suspect that exhaust back pressure or dirty filters are affecting your vehicle's horsepower, then have your local mechanic measure your back pressure and replace your dirty filters immediately. A general car tune up never hurt, either. If you fail to address these issues, then your vehicle's performance will only decrease as you continue to drive.