Jerking of car during acceleration is typically symptomatic of a larger underlying engine and fuel housing problem. Often referred to as hesitation while accelerating, it isn’t always easy to pinpoint what might be going wrong with the engine. After all, the engine has innumerable components. The purpose of this article is to make it easier for you to isolate the issue by discussing some of the most frequent causes of jerking in the acceleration phase.
Clogged Catalytic Convertors
Connected to the exhaust line, the catalytic convertor in your vehicle is responsible for regulating pollutants in your vehicular emissions. In other words, it is a tool meant for reducing your carbon footprint on the planet.
Sometimes, due to rich air/fuel mixtures the catalytic converter gets clogged, resulting in stuttering expulsion of noxious by-products of the fuel combustion process. This clogging manifests itself as a stuttering motion when hitting the gas pedal – there is a slight delay in responsiveness and then a sudden jerk forward.
It is an expensive affair to replace catalytic convertors, so you should be doubly sure if the catalytic convertor is the reason. Some other indicators of a clogged catalytic convertor are unusual tachometer readings due to a reduction in engine power and expulsion of hydrogen sulphide from the exhaust line. Hydrogen sulphide results in a very distinct rotten eggs odour and is hard to miss.
Damaged Fuel Lines
You must have a mental model of what the fuel housing comprises of. Some crucial components that form the fuel housing are fuel injectors, filter and the pump. These play a part in determining the supply of fuel to the engine for the purpose of internal combustion, which really is the life force of your vehicle. Stuttered supply of fuel to the engine will result in arbitrary generation of engine power. It results in differing amounts of acceleration created with the same amount of force exerted on the gas pedal.
However, this is not a very difficult problem to fix. It is always best to start by fixing the component that is easiest to fix – the fuel filter. Replacing the filter is relatively inexpensive and most people can handle the task themselves. On the other hand, fuel injectors are commonly neglected portions of fuel supply line and fuel hoses are generally difficult to clean manually. Thankfully, there are several fuel additives available that will keep these components clean during the course of normal operation of your car itself.
Prevention is better than cure, right?
Poor Voltage Supply
The alternator essentially provides for electricity requirements of the vehicle. It is a common misconception that it is the battery that caters to the electrical process, because the battery really doesn’t have much to do beyond seeing to the ignition spark. After ignition, it is the alternators that keep the juice flowing. Just like any other mechanical contraption, the alternator is subject to wear and tear, which leads to loss in efficiency.
Voltage provided by the alternator is used by the fuel pump to circulate fuel in the vehicle. An old alternator may struggle to meet the energy needs of the fuel pump resulting in a lack of fuel hitting the combustion systems. Poor voltage supply is not a very common diagnosis for hesitation in acceleration making it all the more important to be mindful of it. A good quality multimeter made for automobile is a handy tool that can help diagnose this as the source of car jerking problem. The only helpful fix is to replace the alternator.
Moisture
Sometimes blaming the weather for car jerking is actually right on point. During cold or humid weather, a common experience is condensation of moisture on the inside of the distributor cap. The humble distributor cap performs a critical role – it allows for the transfer of voltage from the ignition coil to the combustion cylinders.
When the distributor cap ‘sweats’, the moisture can often hit one of the points on the rotor in the distributor cap, thus impeding the spark needed for ignition as well as subsequent transfers of energy to the cylinders. The ignition system does exactly what its name suggests – it ignites the carefully maintained air/fuel mixture present in the engine chambers where combustion occurs.
While the obvious way to prevent this is to park your car in drier and warmer spaces, often that might not be possible. In such cases, the only way to fix a moisture problem is to dry the inside of the distributor cap. An easy way to do this is to spray some carburettor cleaner or any other automotive solvent on the underside of the distributor cap.
Final Words
Simply put, most causes of a jerky vehicle can be resolved and even prevented with regular maintenance. Often, the result is simply dirt or clogs. There might be causes other than the ones mentioned above, such as a skewed tyre alignment or spark plug errors, but they are just as straightforward to resolve.
Sources:
- Car jerks forward at high speeds Inspection Service – Your Mechanic
- Top 5 Signs of Engine Trouble – howstuffworks
