Is it possible to read a check engine light code without a scanner? Engine light is on, originally only if I accelerated hard on the highway, now it comes on intermittently and I have a very rough & low idle. I suspect it is an oxygen sensor. If this has been covered before a redirect to the forum post would be appreciated.
Thanks, Michael
07 Expedition Max 256K KM, bone stock

 

If the light is blinking, rather than simply remaining on, you can generally count the blinks. Four quick blinks, a pause, then 3 quick blinks would be 43, for example. In any case, if the vehicle is running, you can take it to Auto Zone, Advance Auto, NAPA, etc. for a free code scan.

 

I would suggest purchasing a code reader, they are pretty inexpensive. I believe Autozone will read them for free as well. I bought an OBD2 reader off of Amazon, it is bluetooth, pairs with my phone, and with the torque app (free) it will tel you any stored or pending codes. You can also clear them from the app as well. Plus it does other cool stuff (real time data from various sensors, etc...) I can't remember what it cost exactly, but i think it was around $20, money well spent. I had similar symptoms it turned out to be a misfiring COP, the scanner helped me pinpoint it.