Most Common Reasons Your Check Engine Light Is On 

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Thank you!

But you need too mention the mileage with these problems because that's a big issue when looking at the problems ?

Hi and thanks for watching! Yep, we live in the countryside, that's the reason. Interferes a bit with the video but I hope people don't mind :-) All the best to you!

Amazing view 😍

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I’m doing same way I block the engine light by my arm and I’m not look this way

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did chek engine light go off emidietly after you change gas cap? and on which car?

@@jaskosijaric4021 Kodiaq & no it didn't go off immediately. After a few cold starts.

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Your welcome and glad the video helped! You're right, in most cars that's the situation. Thanks for the contribution and all the best to you! :-)

Did it just come on and stay on or did it come on flashing? Mine just happened tonight but I also thought after watching this video it’s could be my gas cap as well, since the other day I started my car and I smelled kind of strong gas and could not figure out why but did go get gas a couple days or a day prior.

@@rachelaimer6284 If the check engine light is flashing it definitely isn't the gas cap. That means it's something that needs immediate attention and you should stop driving. It could be you have a misfire if you smell gas. Misfires are when the spark plug in one or more of your cylinders isn't sparking to ignite the fuel/air mixture. This could be caused by a bad plug(s), a bad coil pack(s), clogged fuel injector(s) a bad signal from your ECM. The best thing to do is have it scanned. That will show you the error code that caused the check engine light to come on. Just remember, that only shows you where to start looking. You might pull a P0171 Fuel Trims are Lean. There are a few reasons why this could be. An 02 sensor might trigger it. You DO NOT want to just replace that sensor because there are other reasons that cause a GOOD sensor to send an error code. So many people do this. Then they reset the check engine light after replacing the part only to have it come back on in two days. Remember, it's just a code to let you know what to look at and narrow down the problem so you know you've got it. Vacuum leaks, a bad or dirty MAF sensor, tons of things can be off to trip that light. But...if it's flashing it's warning you that the problem is not good to keep driving. You could do permanent damage to you engine. You can buy a cheap scanner for about $20. More advanced ones run more. But a simple code reader is fairly cheap. I bought one for $20 that gives me the code and live engine data via Bluetooth to my Android. I can look at long and short term fuel trims, (very important on diagnosing how your car is running), misfire codes, 02 sensor readings, Catalytic converter temps. Remember, your cars ECM will make adjustments to things like fuel/air mixture to keep a 14.7/1 air to fuel ratio in your engine. So even though your car is running great you might still have a problem. You just don't know it yet because the sensors haven't hit the max to trip a code and have the check engine light turn on. If you notice your gas mileage has gotten terrible, you smell gas in the exhaust, these are signs that the ECM is making adjustments because something is off. The car will still run great but there's a problem. A vacuum leak after your Mass Air Flow Sensor is allowing un-monitored air into your intake throwing off that 14.7/1 air ratio your engine and ECM want. The ECM doesn't KNOW there's a vacuum leak. It just knows that there is more air than fuel. So, the ECM will send MORE GAS to your cylinders making your fuel trims go crazy. If they hit a max you'll get a P0171 code. Fuel Injection System Too Lean Bank 1 (or 2 if you have a V-6 or V-8). Most likely a loose vacuum hose, Dirty MAF Sensor or even a Dirty Air Cleaner. I know there is a lot of info here and you might not understand most of it. But a sensor code doesn't necessarily mean that sensor is bad. In fact most of the time it doesn't. So my point was to just save you money buying parts you DON'T NEED. You can email me if you have any questions. I'm happy to help anyone save money from rip off auto parts stores that WILL TELL YOU to buy this or that. They are WRONG 90% of the time. I hope this helps you. Feel free to ask any questions you have any.

@@RickyPisano Hi thank you! I do have one more and your response was actually very helpful and anything I didn’t know I just googled to find out so no biggie. When I started it up this morning the light did not appear. Could it be possible that it came on as warning? It is winter and there was a snow storm and I don’t think my grandfather pulled my car in his driveway after letting it warm up, I believe he just started it up and went to park it and then it shut off on him and he floored my gas pretty ruff to get it from the end of his driveway. I will still check as I had no time to do it in the mist of already having so much to do to add on to this. I’m hoping it was just a warning to not do that again or if not something very minor that can be fixed.

@@rachelaimer6284 If it went off and it's running OK then you should be fine. Keep an eye on your gas mileage and if the engine runs smooth. Like it normally does. If something is off the light will come on again. It may have been a very temporary low oil pressure signal because of the cold. That would be my guess by what you described. I wouldn't worry about it if the light went off on it's own. Something like a loose gas cap that triggers it will usually turn back off after a couple of cold starts once it's tightened. No biggie. I think you'll be fine. The newer engines post 2005 or so don't need to be warmed up. They have thinner, usually synthetic oil like 5W20 and when cold the ECU automatically runs the engine rich (open loop) until it's warm and hits operating temp and the O2 sensors kick in (Closed Loop). Then the air/fuel mixture is automatically adjusted by those readings. The old carbonated V-8's, Slant/straight 6's and 4 cylinders had way thicker oil like 10W40 and it would get like molasses in very cold weather and had to be warmed up to pump through the engine effectively. The Choke on the old carburetors would be open to make the engine idle higher on those engines and you actually had a "gas pedal". On these newer ECM controlled engines you don't. The pedal you press is actually an "air pedal" that opens and closes the flap on the Throttle body to allow more or less AIR into the engine as the ECM is in full control of your fuel that enters the engine based on the amount of air entering it at different speeds and RPMs. The air coming in is measured by the Mass Air Flow Sensor or MAF positioned in front of the throttle body to maintain that 14.7/1 air to fuel ratio. I still let my 2005 V-6 warm up a bit though before I put it in gear and take off. I still think it's a good idea to do that when it's really cold out to make sure oil pressure is ok and no warning lights stay on. I think you'll be fine though as long as the light is off and the engine is running like it normally does. I hope this helps you.

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Thank you very much! :-)

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My Nissan won't start I have a code reader hook to it but I don't know what the code means it's 150 9141

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Glad to hear that we could help :-). Thanks for the visit and nice comment

What's the main effect

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Hi David and thanks for watching! You're right the present system has a lot of flaws and is sometimes unreliable, even to the point that some good old thinking and old-school problem-solving does a better job. Perhaps someday a car will have some sort of its own self-diagnostic system which will give more precise information. All the best to you!

It’s not that they can’t make a sensor that tells you, they don’t want to. They want you to have to take it to an authorised dealer. ££

try FIXD

They don’t have a censor that tell you what’s wrong because there’s no money on that if you know the problem then they won’t b able to charge u 500 dollars to tell you there’s something wrong and if u wanna know what it is it’s another 300 dollars and if u wanna fix it then it’s half the cars actuall price

but did they send a man to the moon think about it

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Hi and sorry for the late reply. Thank you for the kind words and for watching, hope the video helps solve the problem 🙂

@@DespairRepair thx for reply ::)

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I hammered a nail thru the cluster to cover it up.

@@Eeddee408 that's to rough mate, you damaged your car!

Thanks, it worked

@@Torsdagskvallsmys I'm so happy I could help, thinking of starting my RU-vid channel

@@casparow123 go for it!

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Hi Firoz and thanks for watching! Certainly, worth the try, hope that any of the tips help!

....sever the wire, to that engine light......

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@@DespairRepair by

No problem, thanks for watching!

Hi, thanks for watching and for sharing, much appreciated 🙂

My check engine light came on but I couldn't get an appointment in town. I went to get gas an discovered my cap wasn't tight? Thank you ❤️

@@ginapereira8948 you're welcome and thanks fpr watching!

I have the light on my mazda 2006 tribute with 90K miles The mechanics said its the air to fuel ratio and are quoting $3,000 to fix a list of different problems lol

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When did the light go off ? Instant or after some driving

@@UltraxHere straight away as far as I remember

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Hi and thanks for watching. Glad that the video helped and that you solved the problem. By the way, nice car you have there.🙂

Hi, thank you for watching and for the nice comment :-) Best regards!

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lmao what??? 😂

Be careful. Or roll a doobie instead.🙂

love this

😂😂😂😂

Did u get a buzz though despite that

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what was your car doing .to make u change gas cap?

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Thank you very much for the nice comment and for watching! Veliki pozdrav 🙂

Disconnect the negative connection from the battery for a minute.

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Hi Roger, thanks for watching and the good comment!

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Hi, thanks for watching and for the kind words 🙂 If you're talking about the pipe for the air intake, yes it can.

Glad that the video helped and thanks for watching! :-)

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Hi and thanks for watching the video! I think that the AA man gave you some good advice. The check engine light is notorious for coming up for minor faults like weak electric connections, loose hose clamps or other while the codes show more serious problems. Anyway, drive the car until the check engine light comes up more often or more serious symptoms appear. Just pay some extra attention in the meantime. Otherwise, you could just end up spending money and replacing parts that maybe don't need to be replaced. This is all from experience, btw. All the best to you and hope the light doesn't come up again :-)

Same exact thing happened to me. My check Engine light came on. Scanned with scan tool. Pulled 2 codes. One was gas cap. The other was bad battery connection. I was just about to get it fixed and the light went off. Drives, idles fine. No power loss.

Hello and thanks for watching! Glad the video helped. I've had a similar case, the only difference was the gas pump wasn't a self- serving one. The worker that poured gas forgot to put back the cap altogether and left it on the roof. Luckily I noticed in the rearview mirror that something fell off beside the car. Since then I always check if the gas tank cap is tightened and is returned properly. You can never be too careful :-)

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Disconnect car battery for few minutes and connect. Might be that computer need reset.

Yes because the light does not turn off immediately

@@mariuszmoraw3571 you can also just disconnect the negative terminal witch is easier.

Check throttle sensor & clean properly.