Check Engine Light - When to ignor, when to go to a mechanic


I just purchased a used car (1999 Chevy Prizm) and after about 25 miles of driving the “check engine” light came on. With other cars I’ve had I usually waited until I had to have some other work done on the car and asked the mechanic to check out why the light came on. I have never been told there was a problem, I’m usually told it’s a computer blip that made the light come on for no reason.

It seems as though half the people I know are driving around in cars with “check engine” lights on. Sometimes the lights go off and on, sometimes they stay on.

So what is the sensible thing to do when the “check engine” light comes on? Does the light ever mean there is really and truly a problem that needs to be addressed ASAP?


When the check engine light starts flashing, that means it’s telling to stop right the hell now.

But if it’s just steadily on, take it to a local Advance Auto Parts and they can read the code there for free. Then, depending on what the code is, get it fixed or leave it alone. Eg, if the code for a misfire comes up, you might want to get it fixed. If it’s a loose gas cap, don’t worry too much about it (tighten the cap, though.)


Think of it this way–When someone ignores chest pain, they may just be experiencing some indigestion. Or that same person may be experiencing a coronary event. Without diagnosis, the decision of whether or not to do something about that chest pain is potentially…well, let’s just say…serious.

With your car, the presence of the check engine light could be something that is insignificant or it could be something that is potentially much more expensive to repair if the repairs are delayed. As has been stated already, getting a free scan at Auto Zone or another auto parts retailer is the best bargain in the business–a free diagnosis of sorts. After getting the code(s) and the verbiage that go along with the code(s), you can post back here with that information and get some specific advice.

Otherwise, as Clint Eastwood said years ago…“Do you feel lucky today? Well, do you?”

Why take chances?


That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code not just their translation into English and post it back here. It likely will have a format like P1234.

Frankly even driving to the next exit with a flashing light or putting OT off until next week with a steady light is foolish.


I agree with Joseph E Meehan, You never want to ignore a CEL. With some of the parts stores checking these codes for free there is no reason not to get it read and fixed. Look at it this way the earlier you get it fixed the less likely hood it would cost you more to repair if you wait. For example if you wait to fix a O2 sensor it is more likely that you are damaging your catalitic converter due to your engine running richer. In turn it costing you more for repair if you just had the first CEL read and fixed.


Why does the original formatting of a post later change? My post (above) originally had paragraph breaks and bold font, both of which have disappeared. The resulting change in formatting makes for less readable text, and that doesn’t help anyone.

Are the web lackeys working on fixing the glitches that remain with the new software?