Please forgive my ignorance here. Our check engine light on dash came on a few days ago. Engine runs fine and sounds great. Is the on board computer set up to signal when a maintenance issue has not been taken care of or is due? I will have the code read. Is this info trust worthy? I changed the oil myself last week. I am an old school guy so just not up on this computer info. This is in reference to the car in my signiture

Hey Bob,If you have a smart phone, down Torque app, and buy a OBDll dongle from ebay. With this app you can read and clear the codes yourself for less than 20 dollars. Not only that, but Torque can be configured to give you real time information from your vehicle. What and how much depends on what the manufacturer has allowed.

did you just fill up with gas. this can cause the fumes from gas tank to issue a light. cant remember for sure, but I think AAmco does it for free

Make sure your gas cap is installed correctly. Some auto parts stores will loan you a code reader to use right in the parking lot. Oil change places have them too.

CEL means some sensor or other somewhere has reported an odd reading. It may or may not relate to anything or everything. Reading the codes will accurately tell you what system reported the error, but it will not necessarily tell you what is wrong. And it can range from gas cap is loose to engine just fell out on the street. It may or may not be related to overdue maintenance issues.Sometimes all you need to do is clear the code. Sometimes the code will clear itself after 3 or 4 (or maybe 10) restarts. But in any case, reading the code is the necessary first step.

I had a similar problem with our Toyota Camry. I had it checked and they told me there was nothing wrong. I disconnected the battery for a few minutes then reconnected. The light stayed off for a few weeks. I did it a few times over about 3 months.The car ran and sounded great.Then the weather got colder and the car wouldn't start. I replaced the battery and had no more problems with the CEL.It's been about two years and everything still works great.Computers can be funny.

CHECK EGINE LIGHT? | Good Sam Community

patperry2766
Explorer II
Dec 04, 2015
Color is critical. The majority of check engine lights illuminate in two colors, either red or yellow/orange. While both are important, a non-flashing red light typically alerts a driver that the car needs immediate attention. Furthermore, a red light could mean that there is a malfunction that is potentially unsafe to the passengers of your vehicle. A red light signifies that you should move your vehicle to a safe place as soon as possible and turn off the ignition. Typically, these situations require your vehicle to be towed to a vehicle repair shop or dealership for an immediate analysis. A yellow light is an indicator that should alert you to investigate the problem. Some check engine lights will flash either yellow or red depending on the make and model of your vehicle. Check your vehicle manual for specific guidelines for your car.

I took this info from another website. A lot of people aren't aware of a 2 color check engine light. If it's yellow, it's usually emissions related.
bguy
Explorer
Dec 03, 2015
Everything that sets the CEL is emissions related. As another poster said the on board diagnostic's job is to control emissions and protect the cat.
Campfire_Time
Explorer
Dec 03, 2015
Did it again! First day with my new hands...
Campfire_Time
Explorer
Dec 03, 2015
Duplicate post. Sorry, nothing to see here. Move along...
Campfire_Time
Explorer
Dec 03, 2015
mtofell1 wrote:
Go to an Autozone (Lots of them around the Portland area) and they will read it and give you a print out for free. No room for making stuff up to sell you parts, as some others have suggested could happen.

It's not that they make stuff up. But they certainly try to sell you stuff. As I said above many codes are generic and aren't necessarily pointing to the exact cause of the code. I used to have them read codes, but man what a hassle. Waste of time going there, often having to wait for someone who has the time to do it, and then having them try and sell you something that you probably don't need.

As said above, if you have an an Andriod phone or tablet you can read the codes, and do far more, for less than $30 for both the app and ODBII reader, and do it in the comfort of your own driveway. Better, if you are on a trip you don't have to hassle looking for an AutoZone or equivalent.
mrgrim007
Explorer
Dec 03, 2015
I bought an OBDII reader on Amazon. Works great, inexpensive and handy to have.
BenK
Explorer
Dec 03, 2015
For sure have it scanned and if that light is BLINKING...bring it in *NOW*...something
is about to fail or already failed and WILL/MIGHT bring down other components to
leave you stranded with a big $$$ bill....
mowermech
Explorer
Dec 03, 2015
I get a CEL on my Dodge quite regularly. Chrysler products can be programmed to tell the codes. without starting the engine, turn the ignition switch ON/OFF/ON/OFF/ON. Leave it ON after the third cycle, and look at the odometer. The code(s) will appear, then it will say (P-DONE).
In my pickup, it always says P-0301, which means #1 cyl. misfire.
I know there is a leaky exhaust valve in #1 cyl., so I ignore the light, and it goes out eventually.
coolbreeze01
Explorer
Dec 03, 2015
mtofell1 wrote:
Go to an Autozone (Lots of them around the Portland area) and they will read it and give you a print out for free. No room for making stuff up to sell you parts, as some others have suggested could happen.

I went to AZ for a code read and ended up buying an inexpensive one. Does the job and has ended up saving me money.
ksg5000
Explorer
Dec 03, 2015
I wouldn't disconnect the battery - just take the car down to local auto parts shop and have them pull the codes --- it's free. Once you get the diagnostic you will have some info to make a decision. Some lights come on to remind you to change oil, oxygen sensor etc ... better to know the potential problem than try and eliminate the light.