Getting gas is usually a routine part of owning a car. You pull up to the pump, fill up your tank, and drive away without thinking much about it. But sometimes, that simple act of filling up with gas leads to bigger problems – like your car not starting after you get gas.
This frustrating issue has many different potential causes. The good news is that with some basic troubleshooting, you can likely get to the bottom of the problem and get your car up and running again.
Common Causes of a Car Not Starting After Getting Gas
There are several components that could be the culprit when your car won’t start after getting gas:
- Bad or contaminated gas – Getting a tank full of bad gasoline with contaminants in it can cause your car to have trouble starting.
- Faulty fuel pump – The fuel pump’s job is to deliver gas from the tank to the engine. If it’s failing, the car may start then die.
- Clogged fuel filter – A clogged filter prevents proper fuel flow to the engine, which can lead to no start conditions.
- Problem with fuel injectors – Faulty fuel injectors disrupt the proper air/fuel mixture to start the engine.
- Improperly sealed gas cap – A loose or missing gas cap allows fuel vapors to escape, which can cause a failure to start.
- Moisture in gas tank – Excess water in the gas tank can stall a car right after getting gas.
- Vapor lock – Heat and pressure combine in the fuel system to create vapor bubbles that block fuel flow.
- Dead battery – Other issues like an alternator problem may kill the battery after a drive to get gas.
- Faulty spark plugs – Without good spark plugs firing, the engine won’t start.
How to Diagnose the Problem
Diagnosing why your car won’t start after getting gas involves checking each component in the fuel and ignition systems. Here are the steps to take:
Step 1 – Check the Gas
Check the quality of the gas you just put in. Is water or another contaminant present? Drain out some gas into a clear container to look for particles. Bad gas is a common culprit for cars that won’t start after filling up.
Step 2 – Check the Battery
A starting issue right after getting gas may point to a battery that finally died on the drive. Use a multimeter to test the battery’s charge, or have an auto parts store test it. Recharge the battery or replace it if it’s dead.
Step 3 – Check the Fuel Filter
A clogged fuel filter will make it hard for your car to get the gas it needs to run. Change the filter if it’s dirty. Many are located underneath the car.
Step 4 – Check the Air Filter
A blocked air filter can also impede proper fuel flow and prevent starting. Remove the air filter and inspect it. Replace if it’s overly dirty.
Step 5 – Check Fuel Pressure
Using a fuel pressure gauge, check that the pump is generating enough fuel system pressure to start the engine. Pressure should be around 30-85 psi depending on the car.
Step 6 – Check the Spark Plugs
Remove the spark plugs one at a time and check their condition. Look for excessive oil buildup or worn electrodes. Replace plugs that are in poor shape or questionable.
Step 7 – Check for Loose Gas Cap Message
Many cars have a separate “loose gas cap” warning light or message. If this light is on, tighten the cap properly to see if it fixes the no-start issue.
Step 8 – Scan for Trouble Codes
Use an OBD-II scanner tool to check for any diagnostic trouble codes (DTCs) stored in the car’s computer. Codes pointing to fuel or ignition problems can help narrow down the issue.
By following these diagnostic steps, you should be able to pinpoint what’s causing the car not to start after getting gas in most cases. If the problem still proves elusive, it’s best to take the car to a professional mechanic for further troubleshooting.
Main Components to Check in Fuel & Ignition Systems
When gassing up your car leads to a subsequent no-start problem, there are several key components in the fuel and ignition systems that should be checked:
Fuel system components:
- Fuel pump
- Fuel filter
- Fuel injectors
- Fuel pressure regulator
- Purge valve
Ignition system components:
- Spark plugs
- Spark plug wires
- Ignition coils
- Distributor cap and rotor
- Camshaft/crankshaft sensors
Issues with any of these parts can prevent your engine from starting properly after adding gas.
Common Causes Overview
Here is an overview of some of the most frequent causes of cars not starting after getting gas:
|No fuel to injectors/engine
|No spark for ignition
|Vapor lock in fuel lines
|Hot weather/engine heat vaporizing fuel
Specific Causes by Car Make & Model
Certain makes and models tend to have their own common issues that can lead to no start right after filling up with gas:
|Long crank time after gassing up
|Clogged fuel filter
|Car stalls immediately after getting gas
|Faulty purge valve causing too much vapor
|Car struggles to start after filling tank
|Failing fuel pump not supplying enough pressure
|Car hesitates and finally starts after gas stop
|Weak fuel pump or clogged filter
|Car won’t start after low tank refill
|Damaged EVAP system
|Car quits shortly after leaving gas station
|Loose or missing gas cap
If you drive one of these vehicles, be sure to check for these known issues after a fill-up leads to no starting.
Steps to Get Your Car Started After Gassing Up
Here is a summary of the key steps to get your car started after a breakdown upon filling up the gas tank:
- Confirm full tank – Make sure the tank actually has gas after fill up.
- Check for fuel leaks – Look for any leaks in fuel lines under or around car.
- Check for gas odors – Strong gas smell may point to vapor lock.
- Check diagnostic codes – Use OBD scanner to read any error codes stored.
- Check fuel filter – Replace filter if it’s dirty or clogged.
- Check fuel pump pressure – Ensure pump provides proper fuel system pressure.
- Check spark plugs – Remove plugs and test for proper spark.
- Test battery – Use voltmeter to check battery charge level.
- Attempt to start car – Try starting again once potential issues are addressed.
With a systematic approach, you can troubleshoot the problem and identify any issues with fuel delivery or ignition that are preventing your car from starting after you add gas.
Preventing Future No Start Problems After Fueling Up
You can take certain steps to help avoid your car stalling out in the future right after filling up:
- Use top tier gas – Major brands like Shell, Exxon, etc. follow the Top Tier standards to minimize bad gasoline.
- Avoid very low tanks – Don’t let your tank get near empty, which risks sediment getting in fuel lines.
- Check your gas cap – Make sure the cap seals tightly to avoid evaporation issues.
- Change fuel filter regularly – A clogged filter is a common cause, so change it per manufacturer schedule.
- Address small problems early – Don’t ignore minor fuel or ignition issues that can lead to breakthrough problems.
When to Call a Mechanic
If you’ve worked through all the common troubleshooting steps but your car still won’t start after getting gas, it’s best to have a professional mechanic look at it. A technician can diagnose elusive engine no-start problems using specialized tools and expertise. They can also safely work on fuel and ignition systems.
Frequently Asked Questions
What should I do if the check engine light comes on after getting gas?
A check engine light pointing to fuel trim and purge valve codes often indicates a problem with bad gas or trouble purging fuel vapor. Drain the tank and refill with fresh fuel. Disconnect battery to reset computer.
Why does my car die when I put gas in the tank?
This points to vapor lock in the fuel system. The fuel pump and lines heat up during driving. When gas is added, it boils and creates vapor bubbles that block fuel flow, causing the stall. Protect the pump and fuel lines from heat.
Why does my car struggle to start after putting gas in but drive fine after starting?
The extra fuel from filling up can overwhelm a weak fuel pump, restricting fuel pressure needed for starting. Once started, fuel demands are lower. Have fuel pressure tested, check pump capacity and filter condition.
How do I know if I have bad gas in my car?
Symptoms of bad gas include hard starting, engine knocking or misfiring, sulfurous smells, and decrease in power and performance. Drain tank immediately and refill with fresh gasoline to mitigate damage.
Can old gas cause a car not to start?
Yes, as gas ages it starts to oxidize and turn to varnish. This varnish can clog fuel filters, injectors, and build up in engine passages. Old gas has fewer combustible compounds as well. Drain and replace with new fuel.
The Bottom Line
It’s alarming when your car won’t restart after getting gas, but in most cases, the cause is a fairly simple mechanical or fuel delivery issue. By methodically checking for spark, fuel and intake problems, you can troubleshoot the no-start condition and identify any worn parts needing replacement. With some basic tools and diagnostics, you can get your car back on the road and avoid future issues by following proactive maintenance practices.