Why Is My Vehicle Losing Power?

If you’ve ever sat behind the wheel of your 4x4 and wondered “why is my car losing power?” then you’re not alone. A loss of power is something that many drivers experience, whether that’s out on the road during a drive, sitting on the driveway starting the engine or while trying to tackle an obstacle when off-roading. 

Losing power in your 4x4 is not like a lot of other issues that can crop up because you won’t necessarily see the cause right away or any smoke to signal that something is going wrong. That leaves a lot of owners scratching their heads and scrambling around for a solution.

This month at Milner Off Road, we’re going to be walking you through seven of the most common reasons vehicles lose power, with items applicable to both 4x4s and cars. These tend to fall into one of three categories: mechanical issues, malfunctioning actuators or a malfunctioning sensor.

Your fuel filter is blocked

Whether you’ve noticed a gradual decline in power when you put your foot on the accelerator or there has been a sudden drop in power, it’s possible that your fuel filter is to blame. Ordinarily, the fuel filter’s job is to keep your fuel system clean and block out dirt, but if the filter becomes clogged then it will lead to either a lower amount of fuel entering the system to power your drive or it could fail and let impurities in the fuel system that make it less efficient.

The solution here is to regularly replace your fuel filter at service intervals to ensure buildup doesn’t occur over time to create the blockage.

Your exhaust has holes in it

If your exhaust has developed holes due to age, this could create a power loss as the gases are required to build pressure in the system and this won’t happen if it’s escaping via various holes. Additionally, a buildup of soot could cause issues in your exhaust, especially since 4x4s were not commonly fitted with a DPF (Diesel Particulate Filter) prior to 2001. 

If your exhaust needs replacement due to deterioration, you can find new exhaust system kits in our online store.

Your MAS has stopped working

The Mass Airflow Sensor (sometimes known as the MAF or MAS) on your 4x4 is the thing that tells your engine how much airflow there is into and out of the system. Without this information, your engine can’t get the optimal mix of air and fuel, leading to a reduction in the power being provided.

You should find the MAS between your intake manifold and the air filter in order to replace a faulty component, with replacements available in our sensors category online.

Your spark plugs need replacing

The job of your spark plugs (or glow plugs in diesel engines) is to provide that spark of ignition for the combustion that powers your 4x4. If these are damaged, clogged or completely dead, then you’ll start to lose power and experience a number of outages, including a failure to start the engine in many cases.

Find everything you need to replace faulty glow plugs in our batteries and glow plugs product section.

Your cylinder compression levels are low

The compression levels in your engine cylinders are what help to combine the fuel and air for ignition. This ignition then powers the cylinders to create mechanical energy from combustion, so if there is an issue with this area of your vehicle, you will likely notice a loss of power overall from your engine. It’s possible the piston rings have also worn, creating low levels of compression.

You can find a variety of cylinder head and camshaft parts in our online store today.

Your fuel pump is causing problems

The fuel pump in an engine helps to pressurise the fuel being injected into the engine, so if there isn’t enough fuel because of a damaged or underperforming fuel pump then you may not get the full power you’re looking for from your engine. Similarly, if your fuel injectors are clogged then a lower amount of fuel will lead to less power.

Find replacement parts for fuel injectors and pumps in our dedicated category to help you get the full potential from your engine.

Your air filter is blocked

Just like your fuel filter, but for the air being drawn into the engine, your air filter is trying to catch all the dirt and debris to keep the combustion power at a maximum. If this becomes clogged with abrasive particles to the point where little air can get in, you’re going to lose a key part of the combustion process.

Buy a replacement air filter for your 4x4 through our online catalogue today.

Here at Milner Off Road, we’ve got decades of experience in getting 4x4 owners the right parts for their precise make and model. You can find almost everything you need to tackle issues relating to a loss of power for your 4x4 in our online store, where we offer rapid dispatch times and delivery worldwide.

For more advice on finding the right part for your vehicle, just give our team of specialist advisors a call today.