I have a 2003 Toyota Tacoma, 4cyl, 5speed. Recently my truck began to run roughly when accelerating or going up hill. Once up to speed or at idle it runs fine. I added on container of dry gas w/ no results. Check Engine light has come on, blinks sometimes, constant others. Need some direction in what to look at. Thank you
Take the truck immediately to have the OBD system scanned for trouble codes.
When there is one stored code, the CEL will begin to light up steadily, and as your Owner’s Manual advises, you should have the problem rectified as soon as it is convenient.
As soon as engine problems begin to mount, and multiple codes are detected, the CEL may begin to blink/flash. Even if it is only one stored trouble code, it is a very significant one because that flashing CEL tells you that the engine is now misfiring, and failure to correct it right away can lead to big problems–including destruction of the cat converter.
Do not delay in having the codes read and then having the problem(s) rectified right away.
I suspect that all of this is the result of lack of maintenance, but only a scan will tell the tale.
Auto Zone, Advance Auto, O’Reilly, and Napa are some places that will likely give you a free scan.