Why your car starts then dies
Many drivers are familiar with the situation when the car starts up and shuts off two or three seconds after starting the engine. This can happen in a variety of situations — cold, hot or even 10 minutes later.
There are many possible reasons for this: electronics failure, problems with spark plugs, clogged exhaust system (catalytic converter) or air filter, faulty gasoline vapor control system and others.
The main reasons why the car starts and then dies:
- Not enough fuel
- Immobilizer locks the engine
- Problems with the ignition wiring
- If the system is not working properly, there is a problem with the electrical wiring harness
- Clogged air filter
- Not enough fuel pressure
- The vehicle has a defective gasoline vapor recovery system
- Improper valve clearance
- Exhaust system malfunctions
- Throttle position sensor failure
- Contamination or breakdown of the mass air flow sensor
- Crankshaft sensor failure
- Bad spark plugs
- Clogged or broken EGR valve
- Timing belt malfunction
Common Reasons Why Car Starts Then Dies and how to fix it: video
Why car engine dies immediately after starting
Here are 15 different reasons why a car engine starts up and then shuts down, and what to do in such a case.
Out of Fuel or Clogged Fuel Filter
Clogged Fuel Filter
The easiest thing to do is to run out of fuel. If the fuel filter was not changed on time, it could be very dirty. The consequence is that the fuel pump can't pump fuel into the system properly.
The anti-theft system has not been disarmed
Alarm or immobilizer system not only locks doors and steering wheel, but also silences engines after starting a couple of seconds. So make sure the immobilizer light is off and the control unit sees the key.
Trouble in the ignition switch wiring
The car starts and in a second stalls, may be due to damage or poor contact connections distributor, ignition coil and / or alternator of the engine or the wear of the contact group of the ignition switch (a common cause on VOLKSWAGEN models).
Damaged high-voltage wiring
The cause of ignition system high-voltage wires failure could be mechanical damage, insulation breakdown, moisture ingress after washing the engine with a water pump under pressure or when driving the car in very deep puddles. This may also cause the engine to run erratically and, under certain conditions, to shut down after a short period of operation.
Severe contamination of the engine air filter
Severe contamination of the air filter
A clogging obstructs the airflow. This creates an over-enriched fuel/air mixture, which makes spark plugs wet with petrol, turn black, and over-fuel. However, in critical situations, when there is very little air, the engine stops working, which is reflected in the fact that it stalls after starting. The method of elimination of this malfunction is trivial — it is necessary to replace the whole or at least blow it out (temporary solution).
Low fuel pressure
Low petrol/salad pressure may be caused by different reasons — full or partial failure of a fuel pump, damaged fuel hoses, clogged fuel filters (both in the tank and near the fuel pump), faulty fuel injectors, failure of pressure regulator in the fuel line.
Failure of Evaporative Emission Control (EVAP) system
Most often the carbon adsorber breaks down or the purge solenoid valve fails. However, the gasoline vapor recovery system may cause the engine to stop only when the engine is «hot», since it does not work at idle speed or when the engine is cold.
The purpose of this system is to capture gasoline vapors so that they do not get into the atmosphere. Thus, they are accumulated in a special vessel, and when the engine starts, they are taken out into the intake manifold and burned in the engine.
In cars equipped with EVAP, electronic engine control units (ECU) are installed, which activate the Check Engine warning light on the dashboard, and when diagnosed, displays an error P0443 or similar, indicating the malfunction of individual system elements.
Intake/exhaust valve clearance disturbed
If there are no hydro-compensators the valve clearances should be checked and adjusted periodically (every 35...50,000 miles). If this gap is not adjusted, the valves eventually start to knock (the noise of the engine increases), and sometimes they get jammed. It is in this case that the engine will shut down after a few minutes of operation, when the engine is hot and will not start again until it has cooled down completely.
The catalytic converter has collapsed
Checking the catalyst with a piece of paper
The catalytic converter cleans the exhaust gases with its ceramic honeycombs, but when its resource is exhausted it can crumble, blocking the work of the exhaust system. As a result, the engine will shut down. Such a problem can be accompanied by error P0420.
Such malfunction is easy to check by simply bringing a hand or a piece of paper to its cut. It can only be fixed by replacing, and this is very expensive ($800 — 1200 for a catalytic converter and from $300 to $1000 for its replacement ). Fortunately, such a problem afflicts only a car with a solid mileage — not less than 93 thousand miles.
Throttle position sensor failed
Throttle position sensor fixes the position of the throttle valve. If it is completely or partially out of order, incorrect engine operation is possible, in particular, unstable idling speed up to the situation when the engine simply shuts down. Such malfunction can be eliminated by replacing the node by checking it with a multimeter.
Contamination or breakdown of the mass air flow sensor
The air mass flow sensor is installed in the intake manifold (after the air filter) and regulates the value of the air mass, which is necessary for the creation of the fuel-air mixture. If this element does not work properly, too poor or too rich fuel mixture is formed, which leads to incorrect operation of the engine.
Its malfunction can manifest itself not only immediately after starting, but also in motion, after a considerable amount of time. Such a problem will be expressed in «hunting», loss of dynamic characteristics of the machine, overconsumption of fuel. In case of contamination, you should clean the sensor element with a special cleaner.
If the mass air flow sensor is out of order, the unit cannot be repaired, therefore, it must be replaced with a new one.
Crankshaft position sensor malfunctions
Checking the crankshaft position sensor with a multimeter
If the crankshaft position sensor malfunctions, the ignition system and fuel injectors become out of sync. As a result, the engine immediately stops after starting. You can find out if this sensor is working properly by checking it with a multimeter.
Spark plugs are out of order
The spark plugs can be old, dirty, failed or of poor quality, i.e. incapable of producing the spark which is necessary for igniting the fuel mixture. As a rule, in this case, the car will start, the engine will jerk and stop.
Dirty or non-functioning EGR valves
Partial failure of Exhaust Gas Recirculation (EGR) may appear not only in the first seconds after starting the engine, but also after several minutes. It depends on the condition of the valve, as well as the operating conditions of the car.
The unit is installed on both gasoline and diesel engines, with the exception of those with a turbine. There are two ways out of this situation — to clean or replace.
Camshaft and valve gear malfunction
This problem occurs rarely, but is possible. It is connected with chain stretching or belt wear. The result of this peculiarity is desynchronization of the intake and exhaust modes. The same malfunction is also possible when the VVTi system fails.
Conclusion
As you can see, there are actually many reasons why the car starts up and stalls. Therefore, in the event that such a situation has occurred, it is necessary to first check the simplest hypotheses and only then move on to more complex diagnostics. Thus it is necessary to recollect, whether there were no problems with any node, listed in this material, in the past. This will help in identifying the «culprit», since the recurrence of faults is not uncommon.
It also makes sense to make an elementary diagnostics with an autoscanner, if the Check Engine light has blinked on the dashboard. This will allow you to find out if there are errors in ECU memory, decipher their meaning and perform appropriate repair actions.
