Engine light came on and the gas cap is stuck

A week ago after filling my gas tank, I drove my car a while and then went on vacation. Upon returning back home, my engine light came on. When I called a car service to make an appointment, I was asked why I was bringing it in and I explained the engine light. She asked if it had come on after filling my tank. She told me to tighten the fuel cap. Before tightening it, I tried to open it and the cap wouldn’t come off – totally stuck! Can you tell me what to do to get the gas cap open?
Experienced mechanics share their insights in answering this question :
Hello. Your particular vehicle has what is known as the smart pin which will lock the gas when the vehicle itself is locked. If you unlock the vehicle with the key fob, the pin should disengage and you will be able to turn the gas cap. If it does not work when you unlock the door, you may have an issue with the smart pin itself.

If that is the case I suggest having a certified technician diagnose the issue with your gas cap and check the smart pin system in particular to see if there are any underlying issues.

How to Identify and Fix Common car Problems ?

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Simply put, if your fuel cap light is on, it means that the computer has detected a leak in the system, typically from a loose gas cap. If this light comes on while driving, pull over in a safe spot and re-secure the cap. Continue driving normally with the light illuminated and it should go off within a day or two.
A loose gas cap will not only let in grime and dirt, but it can allow fuel vapors to escape the fuel tank. These vapors can produce an error in the emissions system, which could cause the check engine light to illuminate.
A loose gas cap will not only let in dirt and grime, but it can also allow fuel vapors to escape. These vapors can trigger an error in the emissions system, which would light up the check engine light.
Once the gas cap has been tightened, the check engine light will reset after several minutes, so drive for five to ten miles to see it reset. It will take some time (5 to 10 miles) for the gas cap to reset after you tighten it or replace a damaged one.
In most cases, successfully repairing the issue that caused your light to come on will cause the check engine light to turn off automatically—but only after 10 to 20 “cycles”.
Bad Gas, What are the Symptoms? If you`ve inspected the gas cap, the problems you are having may be due to contaminated fuel. If a car, truck, or SUV has trouble starting, will not accelerate, or just is not running smoothly, then it`s possible you just have a contaminated tank of gas.
Code P0457 indicates the PCM has detected an EVAP leak, most likely caused by the gas cap.
leaking evap line or faulty evap sensor. Majority of the time it is just worn threading on the cap itself or worn rubber ring of gas cap. Light will turn off, about 20 miles driving after adjusting cap.
When the Check Fuel Cap Light comes on in the dashboard, this may indicate that the fuel cap has not been affixed onto the fuel tank filler tube properly, the fuel cap is missing from the fuel tank filler tube, or that the fuel cap is damaged in some way.
Bad Gas, What are the Symptoms? If you`ve inspected the gas cap, the problems you are having may be due to contaminated fuel. If a car, truck, or SUV has trouble starting, will not accelerate, or just is not running smoothly, then it`s possible you just have a contaminated tank of gas.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Gas cap notification and check engine light came on after getting gas. Car started to sputter and stall out.
ANSWER : Hi there. When the fuel cap is not securely fastened to the tank, it can create vacuum issues inside the tank; which triggers the error code to be stored in the ECU. The error will then trigger the check engine light until that code is reset by a professional digital scanner. If you’re still having sputtering or stalling issues, you should contact a professional mechanic to complete an engine sputtering inspection. This will allow them to diagnose what’s causing this problem and reset any error codes to hopefully correct the issue your Chrysler 300 is experiencing.

Engine light came on and the gas cap is stuck
ANSWER : Hello. Your particular vehicle has what is known as the smart pin which will lock the gas when the vehicle itself is locked. If you unlock the vehicle with the key fob, the pin should disengage and you will be able to turn the gas cap. If it does not work when you unlock the door, you may have an issue with the smart pin itself.

If that is the case I suggest having a certified technician diagnose the issue with your gas cap and check the smart pin system in particular to see if there are any underlying issues.

I have a 2011 Equinox the gas light came on and right after reduce engine light came on. Could this be because the gas is low?
ANSWER : Yes, it is possible for the Reduced Power Warning Light to turn on if the fuel level is so low that normal fuel delivery is interrupted. Low fuel delivery can cause misfiring, oxygen sensors will report out of range readings, and so forth and all of that causes the engine computer to enter a fail safe mode such as "reduced power". Inasmuch as the surrounding fuel is the coolant for the in-tank fuel pump, you should always keep at least a quarter tank of gas in the vehicle. Low fuel levels can cause fuel pump overheating and potentially damage the fuel pump impeller seal and other components. If you need further assistance, please request a warning light diagnostic and the responding certified mechanic will investigate any concerns that you have. If you have further questions, do not hesitate to re-contact YourMechanic as we are always here to help you.

Battery light goes on when I start car then turns off, if I rev engine light comes back until rpms go down. Abs goes comes on/off
ANSWER : Batteries can die due to faults in the charging system so ideally a suspected "faulty" battery should be load tested before a decision is made to condemn it. The only exception to this rule is if the battery is already clearly "old" (greater than 5 years) but even then once you put a new battery in, as a replacement for a "dead" battery, you have to comprehensively check out the charging system. Diagnostic Trouble Code P0460 will result in disruption of the dashboard fuel gauge’s ability to accurately report your tank’s fuel levels. The fuel gauge readings may be erratic, or read somewhere off scale. Vehicles equipped with a low fuel warning light feature may also suffer from erratic low fuel warnings in the event of a code P0460. Unless the P0460 code has been reported alongside other trouble code, all of the vehicle’s essential systems should otherwise function normally. I would recommend that you request a check engine light diagnostic to first resolve the fault causing the P0460 code to set. The check gas cap light warning light could be due a faulty gas cap and/or small leaks in the EVAP system.

2012 equinox reduced power light engine light and traction light came on. Lost a lot of power got home and all light except engine
ANSWER : Your car has what is called a "safe mode" that will be engaged by the computer when it detects that something critical has gone wrong related to any of the major components in your engine chassis or power train. This may be related to a number of things, most of which should have been registered in the computer when the check engine light came on. I recommend having an expert from YourMechanic come to your location to inspect your check engine light and diagnose any codes registered by your vehicle’s computer.

Check engine light refuses to go off after engine replaced
ANSWER : Hello there, you have a long series of issues going on with your 2013 Hyundai Sonata. If you keep getting a repeating oil light on than there is likely a fault in that system.

Since this fault has lasted after the engine was replaced it could be a oil pressure sensor, wiring harness fault, ECU fault, oil pump, oil strainer clogged, or low oil pressure.

To diagnose this issue properly you need a complete vehicle inspection to start from square one and identify the root cause of all this.

Car started to slow down and then the check engine light, battery, and engine oil light came on. What could cause this?
ANSWER : Hi there. It is possible that the battery cable came loose or the wires to the oil pressure sensor has came loose or failed. Check the battery cables and make sure that the terminals are tight and clean. Check the wires to the oil pressure sensor and make sure that they are connected and not broken. If everything looks good, then the oil pressure sensor may have failed. Plus, check the computer for codes and see what is stored. This will lead you to the part that could have failed. I recommend replacing the oil pressure sensor then checking to see if the lights will go out. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, that can assist you with the warning lights that came on.

Idle problems when stopped. Car stops running. 4WD and Check engine lights on and solid. Gas cap tightened to verify
ANSWER : What you are describing sounds like a dirty or faulty mass air flow sensor. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays vital information to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.