This may be a result of a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. Since this valve is controlled by the vehicle’s computer, it will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your idle air control valve.
How to Identify and Fix Common car Problems ?
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If your battery is fully dead, you`ll need to jump-start the vehicle and manually charge it using an external adapter or change it. Fuses – If the car dies while idling but restarts, there`s a possibility that there might be an issue with the fuses of the car. It`s conceivable that one of the fuses has blown.
There are three major causes for a stalled engine: A lack of fuel, a lack of air flow and improper ignition. Running out of fuel is one of the most common causes of engine stalling, but dirty fuel injectors or a plugged fuel filter can also be the culprit. Your engine needs air to run properly as well.
Common reasons for this to happen:
Low fuel pressure, dirty or defective fuel injectors, or broken fuel pump: The fuel pump is responsible for transferring fuel from the tank to the engine.
An engine that stalls when you reach a stop light or while idling may point to a faulty idle air control solenoid (IAC). The computer uses the IAC solenoid to bypass the throttle valve and inject more air, depending on engine operating conditions.
Some of the most common sensors that lead to engine stalling include the mass airflow sensor (MAF), engine coolant temperature sensor (ECT) and manifold absolute pressure sesnsor (MAP). The idle air control valve (IAC) and exhaust gas recirculation valve (EGR) are also well known for causing engine stalling.
The most likely issue is that a component is clogged. A clogged fuel filter is the most common reason, although a loss of power in your car could also indicate problems with the fuel pump or fuel line. Impurities or debris may be blocking the system, which causes the loss of power in a car.
Faulty Battery
A classic reason why your car starts for a second then dies is battery depletion. The car needs electricity from the battery to start. However, if your car starts then dies immediately, then the fault could be a lack of charging or damaged battery.
The Idle Stop and Go (ISG) system automatically and temporarily shuts down the engine when vehicle is stopped and idling to improve fuel efficiency and reduce exhaust gas emissions.
One of the most common reasons for the issue of car turned off while driving is a faulty crankshaft position sensor. The crankshaft position sensor`s role is monitoring the engine`s many moving parts including the crankshaft, engine valves, and pistons.
When the idle air control valve fails, it inhibits the flow of air through the engine. When the car can`t receive air, it leads to engine stalling. The severity of this symptom can range from occasional stalling at first, to stalling immediately after ignition.
Engine stalling
If the idle control valve fails completely, it may leave the vehicle without a source of air to maintain a proper idle. This may result in the engine stalling while operating, and in some cases may result in an engine that will not idle at all, and stalls as soon as it is started.
An idle air control valve, also called an idle air sensor control motor, is an electrically operated valve that controls the amount of air that bypasses the throttle plate in cars with a fuel injection system [source: Autozone]. This causes the idling speed of the engine to change as needed.
Will a bad O2 sensor cause rough idle and loss of engine power? You bet. Moreover, you may also notice poor acceleration, engine misfires, and even stalling. Bad oxygen sensors disrupt all kinds of essential engine functions, including engine timing, combustion intervals, and air-fuel ratio.
A failing camshaft position sensor begins losing its ability to quickly transfer data. Mismatched fuel delivery and ignition timing, even if off by a few milliseconds, will cause your vehicle to sputter, accelerate poorly, lack power, stall or even shut off.
Engine hunting and surging at idle is usually caused by a fuel delivery, air leak, or governor system problem. Cleaning/overhauling the carburettor, adjustment of the governor, and/or changing the air filer may be required.
The main cause of engine stall at high temperature is rapid fuel boiling by increasing fuel temperature. This causes a lot of vapor. Such vapor flows into the fuel pump which leading to decrease the pump load and the current consumption of the fuel pump continuously. This ultimately results in engine stall.
Select first gear. Gently put pressure on the accelerator until revs reach around 1500. Slowly lift pressure from the clutch pedal until you find the biting point. When you are ready to release the handbrake, continue slowly lifting the clutch pedal and putting pressure on the accelerator.
With the fuel pressure gauge attached, start the engine and let it idle. Disconnect the vacuum hose from the pressure regulator; the pressure should drop approximately 8 to 10 PSI. If it does not, suspect a problem with the regulator or its` vacuum supply.
A bad fuel pump may overheat and inadequately deliver gas to the engine, causing it to run hot and turn off while on the road. In this scenario, your vehicle may start back up after overheating and shutting down, only to do the same thing a half-hour later. This scenario is a common sign of a bad fuel pump.
Bad Sensors
One common culprit for this problem is the crankshaft position sensor, which measures the position and speed of the crankshaft. The computer uses the information from this sensor to know when to fire the spark plugs. If the sensor isn`t working, the spark plugs won`t fire, keeping the engine from starting.
The most common reasons a Hyundai Elantra engine stalling are the fuel system, the air intake system, or the ignition system. Search our network of RepairPal Certified shops near you to speak with a technician about your issue.
Engines usually stop suddenly only if they suffer from a lack of fuel or sparks . An engine that stops dead without prior warning has probably had a sudden ignition failure – although if it locks solid it`s more likely to have seized.
If the torque converter is broken, or if there is a low fluid level in the transmission, the converter will not do its job, and the car will be unable to maintain power at low speeds, which causes the engine to shut off. A defective TCS or torque converter solenoid can also cause this issue.