The engine need service soon light was on in my vehicle last week. I suspected it was the bad fuel I put in since it turned on immediately after I pumped at Costco. I was busy and did not have a chance to go to my auto shop. Yesterday, I found the warning light was gone. It contradicts my general understanding that once the light is on, you need a device to turn it off. Will it be something like if you wait long enough, the bad thing will go away by itself?
I would disconnect your battery for 5 minutes. This will reset your car's computer unless you have a Ford. The next time your light comes on take it and get it checked. Advance Auto parts, Checker Auto parts, and Auto Zone usually check them for free, or you can take it to a shop and they can diagnos it for about $50. If you don't get it checked you'll never know what caused the light to go on so you won't know what to fix. It could be O2 Sensor or MAF sensor or a number of other things. I could even be a combination of those things, but only getting it checked will tell you and it'll also reset the computer again.
It sounds like you may very well have had gotten bad gas. Water in gas will reek havoc on an engine and it's sensors. You probably have a car made after 1996, in which it has a OBD2 computer system. You computer will run tests everytime to turn the key on, and if a test fails it will turn the light on. This is what Technicians call a soft code. If the test passes the 2nd or 3rd time run the computer will clear it itself. If the test fails three times in a row, then the code is stored into hard memory in which is called hard code and must be cleared manually. If you light continues to come on, I would have it checked for a possible contaminated oxygen sensor or a clogged fuel injector!
it depends what it was. the check engine light just tells you there's a code stored in the computer's memory. you need the code reader to retrieve the code. my guess is your gas cap wasnt tightened properly after you filled up at costco, throwing a #1443 code, indicating a problem in the evaporative emissions control system (EEC). a loose gas cap will bleed off the vacuum pressure the vehicle uses for the test, causing you to fail the test after you drove away from costco. or it could be some other thing that shows up intermittently. you need to pull the codes stored in the memory to know for sure what happened after you filled up. the gas smell sounds like a seperate problem that occured before you drove away from costco and got an error code. could be a fuel leak somewhere. in newer cars, just turning the key to the on position will power the electric fuel pump. turn off the radio and fan and when you turn the key you'll hear the pump whirring for about a second in your fuel tank, pressurizing the fuel system to feed your injectors the instant you start the car. just turn the key on a few times and leave it on and then go follow your fuel lines to your fuel rail and down each injector and see if you see any fuel leaks. open the hood and use your nose to see if you smell gas. you could have a bad fuel pressure regulator or some bad o-rings, cracked injector, fuel filter
