10 Causes Car Losing/Poor Power when Accelerating and Driving

When a driver puts pressure on the gas pedal with their foot, they expect their vehicle to accelerate faster. The gas pedal causes more fuel to flow to the internal combustion engine so that more power can be generated to spin the wheels. If your vehicle ever fails to accelerate after you step on the gas pedal, then a problem exists somewhere.

The best way to identify the cause of an acceleration problem is to pay attention to the symptoms from the vehicle that you experience. After that, you should compare those symptoms to the potential problems or faulty components associated with them. You can use the list below to learn about the possible causes of an acceleration problem and the symptoms that usually arise from them.

10 Causes Car Losing Power

Below are the top 10 causes of a car losing power when the driver attempts to accelerate it.

1) Weak Fuel Pump

The fuel pump delivers fuel to the engine after taking it out of the fuel tank. It also ensures the pressure of the fuel is just right when it is delivered.

If the fuel pump stops working correctly, you’ll have a situation where the fuel pressure is terrible or not enough fuel is delivered to the engine. Either way, it will cause acceleration problems for the vehicle.

2) Clogged Fuel Filter

The fuel filter screens out the impurities from the fuel before it reaches the engine. It serves as a barrier before the fuel reaches the engine. All of the contaminants and debris will accumulate on the filter as time goes on.

There will eventually come the point when the accumulation of impurities on the filter prevents any more gasoline from passing through it. If gasoline cannot get through the filter completely, then it will cause fuel deficiency in the engine. The result of this will be a reduction in power as you attempt to accelerate.

3) Clogged Exhaust Pipe or Catalytic Converter

When exhaust gases are generated from the internal combustion process of the engine, the catalytic converter attempts to remove the most dangerous toxins from them. Some of the exhaust gases get recycled back into the engine. The rest of the exhaust gases are released through the exhaust pipe.

The exhaust pipe or catalytic converter might get clogged after many years of use. Once that happens, your vehicle won’t generate as much power anymore until those components are cleaned or replaced.

4) MAF Sensor Failure

The Mass Airflow Sensor measures how much air goes into the engine. After that measurement is conducted, the sensor sends the data to the Engine Control Unit. Based on the measurement, the unit will determine how much stress is being put on the engine.

The balance of air and fuel in the combustion chamber depends on this calculation. If the MAF sensor were to fail, the unit wouldn’t know how much fuel to send to the engine. Then your vehicle’s performance will suffer.

5) Engine Low Compression

Adequate cylinder compression is essential during the combustion inside the engine. But if you have low compression for some reason, then you will have low engine power generation. You need to fix the compression problem if you want more power to be generated again.

Read also: 5 Best Aftermarket Oil Coolers for 6.0 Powerstroke Diesel Engines

6) Ignition Coil Malfunction

The ignition system of every vehicle has an ignition coil in it. The purpose of an ignition coil is to convert 12 volts of electricity into 20,000 volts of electricity. The latter is the amount of voltage it takes to ignite the air and fuel mixture within the internal combustion chamber of the engine.

If you have a bad or malfunctioning ignition coil, you would have less than 20,000 volts of electricity flowing to the internal combustion chamber. It would not be enough to ignite the air and fuel mixture and generate power for the vehicle.

7) Bad Spark Plugs

Spark plugs are what generate an electrical spark for the air and fuel mixture in the internal combustion chamber of the engine.

First, an electrical signal from the ignition coil is sent to the spark plugs. After that, the spark plugs send an electrical spark to the engine. If the air and fuel mixture is ignited adequately, it will generate enough power for the driver’s needs.

8) Bad or Clogged Injectors

Fuel injectors are associated with the fuel system of any gas-powered vehicle. Their responsibility is to spray fuel into the engine and manage how much fuel the engine receives. The Engine Control Unit is what ultimately controls the fuel injectors and their spraying.

If the fuel injectors become bad or clogged, then fuel cannot get sprayed into the engine until they are cleaned or replaced.

Read also: 10 Best and Cheap Air Impact Wrenches Under $100 and $200

9) AF or Oxygen Sensor Malfunction

An oxygen sensor calculates how much oxygen is in the exhaust gases after emitting from the internal combustion engine. Once the sensor has this information, it sends the calculation to the Engine Control Unit. This information helps the unit keep a steady air-to-fuel ratio in the engine, so you have the right amount of air and fuel mixing together.

If the oxygen sensor malfunctions, it will send the wrong oxygen calculation to the Engine Control Unit. With a lousy oxygen calculation, the engine will perform more poorly when you step on the gas pedal. The Engine Control Unit might cause too much or too little air to enter the engine, depending on the calculation.

10) Bad Engine ECU

The Engine Control Unit is the central computer of a vehicle. It communicates with various sensors throughout the vehicle to manage all its vital components and systems. You cannot have a functional vehicle without a functional Engine Control Unit.

It is rare for the Engine Control Unit to go bad, but it can happen unexpectedly. When it does happen, you could experience problems with just about any system in your vehicle.

Perhaps your Engine Control Unit will fail to manage your fuel system correctly, causing it to provide less fuel to your engine than needed. Then you will experience a lack of power if this happens.

Read also:

Car Losing Power? Use These 5 DIY Tips to Investigate the Cause

Have you felt your car losing its power? Does the acceleration or torque feel less keen than it was? There are a number of things that could be behind this, but the good news is that you don’t necessarily need to pay a mechanic to get to the root of it. There are several simple things you can check yourself to try and determine the reason for the power losses.

1. Use an OBD Diagnostic Tool

While engines are still highly mechanical, their operation now depends more than ever on the car’s on-board computer. Via that system, you can use an OBD (On-Board Diagnostic) scanning tool to look for data related to the engine and hopefully find what’s wrong. The OBD-II technology, as it’s known, has been a standard feature of cars since at least the mid-1980s. The scanners were previously very costly, but now available on Amazon for good price. I recommend you to use LAUNCH OBD2 Scanner -CRP129E Scan Tool. This tool is very complete and give most accurate result, also works on most US-Based Cars. Buy at amazon >>

You’ll find the port to plug in located under the driver-side dashboard. Plug in and follow the device’s own instructions — scans are typically as simple as pressing 2-3 buttons max. — and examine the results. It can check across multiple systems like the injectors spread duration, combustion processes in your cylinders and much more.

2. Test the Engine Compressor

Using a best compressor testing kit, you can check each of the cylinders on your car to see if the power loss problem is coming from one of them. Follow these steps:

  • Start by removing the fuse EFI system to prevent firing accidents during the test
  • Remove the first ignition coil and spark plug
  • Insert your compression tester as instructed by your product instructions
  • Crank the engine and you’ll get your reading
  • Repeat the process for your other cylinders

To do the “cylinder compression test” by your self,  I recommended you to use INNOVA 3612 Compression Tester. You can Buy it at amazon >>

3. Check for Exhaust Clogs

Your car’s exhaust pipe and/or catalytic converter can all become clogged up as they do their work. Such a clog prevents the system from operating at peak capacity. As with most components in your engine and exhaust systems, when one part isn’t working correctly, the other parts also begin to suffer. Ask a friend to rev your car for you and carefully place your hand over the mouth of the exhaust — being careful not to touch it as it might be hot — to feel for air pressure. If you feel a great rush of air emerging, then it’s likely not clogged, but if it feels weak, then an exhaust clog may be the problem.

4. Take a Look at the Spark Plugs and Filters

A faulty or fouled spark plug, while still appearing to function on some level, will not deliver adequate voltage for optimum running. Locate the spark plugs and check their heads. Do they look blackened, corroded or otherwise unhealthy? If so, that might be the cause of your power loss.

Filters, too, have great bearing on performance. Clogged air filters mean that an insufficient amount of air is making it into the combustion chamber. Clogged oil filters mean that oil is not being cleaned of impurities as it lubricates the engine. It goes on. Always ensure filters are changed properly and in a timely fashion.

5. See if the Fuel Pump Has a Problem

If your fuel pump isn’t getting enough gas to where it needs to be, then your car’s performance can be quickly impacted. The problem is either the fuel pump itself, or the power that supplies it. Start by checking the fuse to your fuel pump. If it’s damaged, then that would explain the ineffective pump.

If the fuse is working fine, then you to do a pressure test on the pump. If you hook up a fuel pressure gauge to the pump test point (usually located close to the fuel injectors), and then have a friend start the engine, you can see the pressure rating. Let the car warm up a bit first — while it’s warming up you can look up the proper pressure rating in your manual — and then rev the engine to get a pressure rating. If it’s lower than it should be, then the pump might need replacing.

To test the pressure of fuel pump, I recommended you to use BETOOLL Fuel Pressure Tester Gauge Kit. You can buy it at amazon >>

When in Doubt – Get More Help

These tips are perfect for those with some knowledge of cars and the confidence to try DIY repairs. If, on the other hand, you feel less sure about it, you could perform some of the simpler checks yourself before you take it to a mechanic. You could then share your findings with them to help them narrow down and repair the cause more easily.

You May Also Like