For sure, having a car that stalls after getting gas is very frustrating. At times, when you fill up the gas tank and almost immediately pull out of the gas station, the vehicle sputters, misses, or hesitates.
More often than not, the engine just stalls. You are stranded, your journey is abruptly disrupted, and this problem is already getting annoying.
An effective engine requires a fairly rich fuel mixture to start and idle smoothly while it warms up. However, what do you look for when the vehicle shakes or sputters? This article serves as a guide in establishing the causes for this issue.
1. Low-quality fuel
This is a common cause why the car stalls when refilling. A fuel that has bad additives damages your car in many ways, over time.
2. Contaminated fuel
Another common reason is contaminated fuel with other fuel types or water that will prevent the car from starting or shut down after refueling. If you notice the following symptoms immediately after refueling, you might have added contaminated fuel:
- Misfiring, backfiring, or pinging;
- The engine is harder to start than usual;
- The engine is running rough or not performing;
- Engine check light is illuminated.
In case you have a suspicion that you have added contaminated fuel, the first thing to do is to call a towing company, or contact a servicing dealer or a local mechanic for verification.
It is advisable to not drive the car to the mechanic or a repair shop, instead call roadside assistance or you should tow the car to an appropriate repair shop. Alternatively, using cars equipped with contaminated fuel detectors will help a lot in identifying that fuel.
Depending on the severity of the contamination, you may have to clean up the tank, after draining the contaminated fuel. Before adding clean fuel, the tank should be deep cleaned to remove all sludge, residue, or contaminants.
3. A bad fuel pump
For a car to start, appropriate fuel pressure is vital. The fuel pump keeps fuel from moving from the tank into the combustion chamber of the engine and runs continuously every time the engine is running.
Basically, the pump has more mileage than the car and thus is prone to wear out over time. A failing fuel pump will make the car stall even after refueling.
Cars have Electronic Control Units (ECUs) as safety features. An ECU will shut off the fuel pump that is not operating properly even when the engine is still running.
4. A bad or failing Electronic Control Unit
Although a rare cause, if the car’s computer does not work properly, the damaged ECU may instruct the fuel pump or other part to shut down the car.
Because it is a hard issue to check and fix, this should be checked thoroughly at an authorized dealer with original software for your specific car to get good results.
5. Evaporative control system
Another common cause why the car stalls after refilling, the evaporative control (EVAP) system comprises many components, including the plunger valve. EVAP has the role to capture fuel, purge it, and store fuel vapors that leak from the fuel storage systems.
Sometimes, if you have an air leak in the evaporative control system, the mass airflow (MAF) sensor may not establish the volume of air that enters the engine. In addition, the manifold absolute pressure (MAP) sensor may not determine the density of the air.
Depending on the size of the air leak and the engine’s operating loads and speeds, this may result in under-fueling or over-fueling. Also, the catalytic converter could be damaged. A defective fuel or refuel cutoff valve hinders the fuel from flowing, and the refuel valve makes the gas pump stop, causing the car to stall.
The best way to deal with this issue is to engage an expert technician to diagnose the starting and stalling challenges.
6. A faulty fuel gauge
This is also a rare cause, especially if the car has an electronic fuel gauge. For some reason, when refilling, the gauge does not work as it should and it can send false signals to the ECU that the car has no fuel, causing the vehicle to stall for safety reasons.
Some helpful tips when adding gas
When the tank is completely filled, the best you could do is to allow the pump to shut off automatically. Do not add more fuel after the initial shut-off. Overfilling the tank by filling it to the brim can cause damage to the evaporative emission systems.
The system is made to process fuel vapor and not liquid fuel to prevent hesitation. At your next fill-up, just fill the tank until the pump shuts off. Once the pump shuts, kindly do not consider adding fuel.
Stalling problems are not fun. Not only does it disrupt your travel, but it also poses a safety risk. If the engine stalls when driving, the car will first lose power steering followed by the power breaks.
The first thing to do is to apply the foot breaks and slowly steer to the side of the road. Let those around you know by turning on the hazard lights. After turning the hazard lights, try to restart the car.
If the vehicle does not start, call a mechanic to sort out the issue or tow the car to a repair shop to fix it. If the engine stalls while your car is at an idle speed, it may be impossible to steer it to the side of the road.
If you are caught up in such a situation, turn on your hazard lights and contact roadside assistance or the police to assist you to safely get the car out of the road. It is not recommended to get out of the car to push it while in traffic.