Car Won't Accelerate

Wondering why you have problems with your car? The internal combustion engine in modern automobile is very sensitive to any type of malfunction. There are many different components that must work together for your engine to perform. Issues such as wear and tear and a lack of regular maintenance can cause acceleration problems. If your car has acceleration problems, read on to find out how to solve the problem.

Causes of Lack of Acceleration

When the car struggles to accelerate, the problem could be related to many things. As fuel is needed to go faster, fuel issues are a number one cause. In manual transmissions, clutch problems are also common reasons for acceleration problems. Here are the common reasons why your car will not accelerate:

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Bad fuel filter The fuel system relies on regular maintenance to make sure clean fuel is being pumped into the engine. When dirt and grime builds up in the system, the engine will be struggling to accelerate. A dirty or clogged fuel filter (view on Amazon) causes a loss of pressure and less fuel flow. (If the pressure is high yet the flow of fuel is low, it is not the fuel filter. There may be a problem with the fuel pump)

When the fuel is not clean there is trouble starting the engine as well as in trying to accelerate. The engine is not receiving enough fuel because the fuel filter is dirty, clogged, or damaged. The fuel filter may plug, stopping the vehicle from moving at all. The plug helps save the engine from operating in the worse conditions.

LeaksThe ECU configures the ratio of air to fuel in your engine. When there is a leak, the configuration of the ratio is inaccurate. The primary areas where these leaks occur are usually found in the intake manifold, vacuum hoses (view on Amazon), or the blow-off valve. The air pressure gauge will read that there is no pressure buildup or there is no hold for less than one second.

The vacuum hose is a common place for those problematic leaks. Cars have several vacuum hoses and any one can be damaged. Leaks interrupt the air/fuel mixture flow and increase fuel consumption because of cracks, splits, or loose clamps. The increase in fuel consumption causes higher EGTs which translates the system does not get enough air. The air/fuel flow has become unbalanced which interrupts the throttle body pressure. The leaks cause high idle. When the vacuum hoses are damaged, the check engine light should activate.

Bad clutch Automobiles are designed with different types of clutches, to include friction, cone, wet versus dry, centrifugal, and multiple plates. The self-adjusting clutch (SAC) (view on Amazon) prolongs the clutch disc service life. As the disc wears down, the clamp load remains the same. The non-self-adjusting clutch has shorter life cycles than the self-adjusting. The clamp load will decrease as the disc thins.

The clutch is the primary reason why your car will have acceleration problems. A slipping clutch can severely damage the drivetrain. The clutch may be damaged or it is just worn out. When this happens, it changes your driving experience. Acceleration problems usually start in first gear when you try to accelerate. The vehicle is only moving slowly; however, it seems as if the engine is racing.

There should be plenty of free play in in your clutch. A hydraulic clutch comes with several parts to include the master and slave cylinders, reservoir, and hydraulic line. The clutch relies on frictional forces to engage and disengage the power transmission from the driving to driven shaft. The clutch fork helps the clutch engage and disengage the clutch. When the pedal is depressed in manual transmissions, bumping and grinding noises can be heard. This can also happen when the gear is in neutral. A major problem with the clutch is when the shaft continues to spin when you release clutch pedal. The shaft bearing may be worn out so the clutch disc remains engaged. The clutch fork may be malfunctioning. Another common problem is that lubricant is dried out.

Bad fuel pump – Most internal combustion engine designs still have the fuel filter in the fuel tank or along the fuel line. The filters keep debris out of the engine and out of the transmission. So, when the fuel system has a problem, the vehicle struggles to accelerate. Fuel is pumped through the fuel filter by the fuel pump under pressure. So, when the fuel pump is not working as it should, it will affect the fuel filter performance.

Bad catalytic converter – The catalytic converter has oxygen sensors and changes the harmful elements from the exhaust into elements that are less harmful elements by using palladium and platinum as the catalyst. When the converter goes bad, it directly affects the rate of acceleration and your car will consume more gas. The catalytic that is damaged or worn out the converter does not burn the hydrocarbons in the exhaust. This means that the sulfur breakdown that comes from the engine is not occurring anymore. Not only will the acceleration struggle, your car will also be running rough, sputtering and stalling, and emitting a strong odor that smells like rotten eggs.

Bad timingSignal timing and the flows can become unbalanced. That is a major shift which affects engine performance. You will notice that your car idles roughly when you come to a stop. You will also experience heavy vibrations which also take away your engine’s power, and the car will exhibit poor power when you press the pedal. In extreme cases, your car will even stall when the throttle is pressed. The throttle body plate will open and close at very fast rates. You may be able to drive your car like this for a short time; yet, the handling will be unpleasant and sooner or later the engine will shut down.

Engine sludge – Most cars develop some degree of corrosion or buildup just from day to day use. The more you drive, the more oil your car uses as well as the accumulation of trash, water, and anything else that can build up under the hood. As the oil heats up from the extreme heat, it leaves carbon deposits. However, build up over the long term is not good. Engine sludge is the worst kind of buildup and it is commonly seen in cars that are inspected regularly. Engine sludge causes other parts of the car to become damaged or to malfunction. If the buildup is a big enough problem, the engine will fail or it may not start up at all. The debris oxidates the oil, and changes to a sticky gel. The oil and fuel filters cannot process of all the debris that has accumulated.

Bad driving habits – The way that you handle your car on the road is a major factor in how long the parts will last. When you drive hard, many things can happen to affect the acceleration, some of which have been covered in this article. Driving gently means you will get much more out of your engine, your brakes, and the cost of fuel.

You Treat Your Car Badly – Most vehicle owners understand that a vehicle must be inspected and serviced from time to time, as referred to as routine maintenance. For those who don’t, the likelihood of problems that cause acceleration problems is extremely high. If the vehicle is not inspected routinely, small problems can escalate to major problems that are much more expensive to fix. This is also true for vehicles which sit for long periods of time.

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Symptoms of No Acceleration

There are symptoms that point you to why your car is no longer accelerating besides the lack of acceleration. Here are the most common symptoms that at least let you know that there is problem:

Warning lights – Warning lights on your dash are a good starting point in figuring what is wrong. There are different warnings for oil, brakes, fuel and so on that indicate where the problem is. The engine control module calculates the amount of fuel that needs to go to the engine with the Fuel Rail Pressure Sensor. When any of these systems has a problem, the Check Engine Light (CEL) will usually activate on the dash. It may be something other than the engine but it affects the engine performance. When a filter is dirty or clogged, and water-in-fuel sensor finds a problem and the ECU will place the engine in Limp mode.

Use OBD2 Codes – The OBD2 Scanner (view on Amazon) can be used to determine what is malfunctioning. The scanner has several codes that relate to the fuel system and acceleration. They are the same codes that your mechanic will look for if you take your vehicle to a repair shop. A common DTC that you may get is the P0171 “System Too Lean (Bank 1)” code. This trouble code shows when the first bank of your engine becomes a weak running engine or that it is likely there is a vacuum leak. The he P0171 code will also show if you have a clogged fuel filter.

What to Do to Fix No Acceleration

There are things you can do to diagnose why your car has not been accelerating as it should. Inspections and diagnostic tools are the best approaches. Here are the most common solutions to acceleration problems in your vehicle:

Try using cleaners – The contamination in the fuel filter and the fuel injectors may be diluted by using a fuel injector cleaner or most fuel system cleaners. Using the cleaners is also ideal when the contamination is inside the fuel tank. Using cleaners is only a temporary solution until you can have your vehicle inspected by a professional.

Replace fuel filter – Just as with any other parts on your vehicle, when the fuel filter is no longer working properly it is time to replace it. If you know about cars you can remove the bad filter yourself and replace it with a new one. If not, you can take your car to the repair shop and have the bad fuel filter replaced. You may still have a warranty on the old part a warranty on the new part. Fuel filters are not very expensive although they may be difficult to access. It is better to replace the filter rather than to rebuild it or clean it.

Bleed the clutch – It is no good to have air inside the hydraulic system. For this problem, bleeding the clutch is often what the solution is. When you press the pedal, the master cylinder forces hydraulic fluid through lines located in the slave cylinder. Bleeding the clutch is a process of removing air from the hydraulic system. Use a vacuum pump to push the air through the fluid line into the bleeder valve. The bleeder is located on the slave cylinder. You should use a clear tube to be able to actually see when the all of air is gone.

Top off – Tractor trailer drivers should make sure to keep diesel fuel topped off to prevent water condensation. Other problems could be a bacteria and clogging. When the filter is replaced, cut the old open and observe the type of activity going on.

Maintenance Inspections – Your local automotive professional is also a good bet. You can make sure the clutch is working properly by having regular maintenance performed.