As the main driver, you know better than anyone how your car runs, so when it loses power, you’ll be the first to spot it. So why does your car lose power? Well, typically, it’s down to four main areas: fuel deliveryignitionexhaust circulation, or engine issues. The final possible culprit is a faulty cooling system.

To get your car back to full power and its regular performance, first, you’ll have to pinpoint the problem. Fixter is ready to help. We’ve got an excellent network of qualified mechanics ready and waiting to get your car back to its optimum performance.

Why does a car engine lose power?

There are plenty of parts that will cause your car to feel sluggish when they stop working correctly: choked up fuel filters and injectors, backfiring or clogged exhausts, blocked catalytic convertors, loose timing belts, failing spark plugs and more. The list is pretty long, including minor, simple issues, right up to severe and costly problems.

They can be mechanical, electrical, electronic, or just down to poor maintenance and upkeep. Whatever’s causing your car to run slower than usual, you need to fix the problem before it leads to real and long-term damage.

What are the common causes of car engine loss of power?

Problems with the fuel delivery

Risk level – Medium

What to do – Locate the problem part and have it cleaned, repaired or replaced.

One of the most common problems with loss of power is something preventing the smooth flow and delivery of fuel into the engine. It could be down to your fuel pump, clogged fuel injectors (they collect dirt over time), a blocked DPF (diesel particulate filter—a component that burns off debris, generally at higher speeds), or finally, the king culprit, a clogged fuel filter.

The fuel filter is designed to prevent dirt and debris from entering the fuel system. Over time, they become clogged with all the contaminants they capture, and if you don’t replace them, they’ll slow down the delivery of fuel, causing poor engine performance.

Issues with the exhaust system

Risk level – Medium

What to do – Have the exhaust checked for blockages and leaks.

To operate at maximum efficiency, your engine needs to clear the exhaust gasses and take in clean air for the next combustion cycle. With a faulty exhaust system, your engine is effectively choked, preventing it from reaching full power.

A backfiring exhaust is the result of a poor fuel and air mix, with the unburned fuel igniting on the hot metal of the exhaust. Backfiring is usually a symptom of a faulty fuel pump.

Problematic blockages can happen throughout your entire exhaust system, but commonly in the catalytic converter. A clogged cat will back up exhaust gasses, causing poor performance.

Engine problems

Risk level – High

What to do – Have a professional determine the cause and correct it immediately.

Given that it’s your engine that powers the car if there’s a drop in power, that’s one of the first areas to check. So what are the components that can cause a reduction in power? Well, your timing belt, turbocharger, anything that drops pressure and causes poor compression, and even a choked up air filter.

There are many possible causes, and pinpointing them isn’t easy for anyone without the correct experience or knowledge.

Electrical and ignition issues

Risk level – Medium

What to do – Carry out a diagnostic test to check each electrical component.

Getting the fuel into the engine is only part of the battle; igniting it is another. Worn, damaged or dirty spark plugs will cause a loss of power, as will problems with ignition coils that power the plugs.

Your car’s computer calculates the timing of the injector and ignition systems to control the camshaft speed. Issues with the sensors can throw the whole thing out of whack, resulting in—yes, you guessed it—loss of power.

Overheating due to a failing cooling system

Risk level – High

What to do – Seek attention ASAP, and stop driving when the temperature reaches dangerous levels.

An overheating engine affects engine performance and power output. It’s also one of the most evident indicators of serious engine problems. If your water pump, timing belt, radiator or other associated part is on its way out or failing in its job, it could mean the end of your engine if you don’t rectify it right away.

How do you restore engine power?

Often, a new fuel or air filter will bring your performance back to normal. At other times, you may need to run a diagnostic test to find out why your engine light has suddenly illuminated at the same time as the power loss developed. The only way to restore prime performance is to fix the problem causing it.

What are the leading causes of engine power loss when accelerating?

Most power loss problems under acceleration are the same as those we’ve already discussed. Clogged fuel and air filters, catalytic converters and particle filters—they’ll all cause a drop in power as you put your foot down. MAF and oxygen sensors are also common causes, as are faulty fuel pumps and clogged injectors.

Why does my RPM rise, but my car fails to accelerate?

A fluctuating RPM is most commonly associated with faulty spark plugs. Worn plugs cause misfires, and as well as leading to a drop in power and engine vibrations, they’ll display erratic RPM readings.

Do car engines lose power over time?

Like any mechanical system, each component that passes against another is prone to wear and tear over time. Your engine is no exception. Whether that wear is in the valve train, piston rings, pistons or anywhere else in the process—eventually, after thousands of miles of motoring, that wear could be severe enough to cause a drop in performance.

To maintain your best chances of extended engine life, we suggest regular servicing, keeping your engine oil clean and uncontaminated, meaning less friction for your engine components to contend with.

If your car is dropping power, one of our mechanics will find out why. Book in with Fixter, and we’ll run a diagnostic test or carry out a mechanical examination. Once we identify the issue, we’ll explain how we can fix it and what it will cost.

About Fixter

Fixter is revolutionising the car maintenance industry, one repair at a time. Fixter was founded to make car maintenance as easy as booking a taxi. Digital, transparent and stress-free, with world-class customer service. Since launching in Manchester in 2017, Fixter has expanded to more than 100 towns and cities across the UK and provided thousands of car owners with honest, convenient and affordable car repair services.