Pet Peeve #63: The “Check Engine” Light

CEL_RedA few days ago, the “check engine” light appeared on my dashboard. So far I’ve refused to heed its warning–I don’t have time to drive my car to a repair shop and leave it there for a few days just so they can plug a machine into it to tell me what’s wrong.

I’ve been trying to figure out why the check engine light bothers me, and now I know: It’s an piece of technology that isn’t as smart as it should be.

The way the check-engine light should work is that it should tell you what’s wrong. If you can plug a separate machine into the car, that same machine could be built into the car or even stored in the cloud and connected wirelessly.

Granted, my car is a 2003 Camry. It’s quite possible that cars manufactured in the last decade already have this function. If so, I’d love to hear about it.

9 thoughts on “Pet Peeve #63: The “Check Engine” Light”

  1. You don’t have to take it to a repair shop. Go to AutoZone, and tell them your check engine light is on, they will bring out a little gadget that will talk to your car and tell you what’s wrong inside of a few minutes.

    You may still end up having to go to the repair shop, but you’ll know what’s up going in.

    • Thanks Joe! That does seem faster than leaving my car with a shop for several days, and I appreciate the advice. I also tried to get AAA to come run the diagnostic, but apparently they don’t have the device.

      Regardless, I wish the device was built into the car! The car knows something is wrong–why won’t it just tell me what it is? 🙂

      • Also, there is a thing you can plug into your OBDII port and leave there that does sync with an app on your phone to do diagnostics. We used to sell them at Advance for about $80. Not the best fix in the world, but will work with nearly any car 1996 and newer.

        Ps, check your fuel cap and make sure it’s tightened all the way. Probably 80% of all the “no symptoms but a check engine light” customers I used to have were “Evap emissions small leak,” which usually means the fuel cap wasn’t tightened up after the last time the car owner got gas.

        • Morgan: Thank you so much for this advice! I’ll definitely check the fuel cap to see if that’s the issue. I also thought about opening the hood of the car, but I’m not a car guy, so it would literally have no impact. The engine could be missing and I’d be like, “Yep, everything looks about right here.”

          That’s good to know about the diagnostic tool. I may have to get one of those.

  2. I agree with you that the technology is well overdue for a remake and takes away power from the average driver who is at the whim of a mechanic to tell them what is wrong. Auto makers have yet to update this technology, with some consumers believing this is to keep people in the dark.

    The good news, at least to diagnose the problem, is that you can simply stop into a local auto parts store (Auto Zone, Napa, etc) and they will happily plug in a reader to tell you what the error message is. If you wanted to do this yourself, you can also purchase an OBDII Code Scanner from Amazon for less than $20.

  3. My 2015 Nissan LEAF SL has this capability. For $10 on Amazon, I bought an OBD-II (on board diagnostics) dongle that plugs into that port (under the steering wheel and towards the front of the car) and connects to an app on my Samsung Galaxy Note 4. That app, LEAF Spy Pro ($15), can read the diagnostic codes from the engine and convert them to English for me, along with a whole bunch of information about the car; VIN, mileage, elevation and speed, battery capacity, charge, and state of “health”, tire pressure, battery temperature, and range left to reserve at my current miles per kWh. There is a free version of the app that doesn’t include some of the information, including the codes from the OBD-II computer, but even a single service call saves every penny of that $25 investment, plus it’s pure-geek fun to know exactly what’s going on with the car.

    But my car doesn’t have a “Check Engine” light because it doesn’t have an engine. 🙂 It has an electric motor, a component very unlikely to fail because of its simplicity. I got the LEAF after my 1999 Camry LE V6 was totaled in an accident, and I am so happy with this car! It is more spacious than the Camry, MUCH quieter (nearly silent), and has creature-comfort features like heated steering wheel, heated seats, and a very intelligent heat-pump-based climate control system, super efficient when compared to a traditional air conditioning/heat set up (the LEAF has no radiator to draw heat from). Maintenance is trivial; rotate the tires every 7500 miles, check the brakes every 50k miles (and experience suggests, replace about every 100k; regenerative braking by the motor means that you use the physical brakes much less), replace the cabin air filter and have the battery inspected annually. Yes, there are virtually no fluids to change; apparently, that heat pump has a fluid that has to be replaced at 125k or 15 years (!!)

    If most of your driving is in-town, or you can wait 2-3 years to replace what you have, consider an electric car next time, Jamey. Range is increasing, the reliability is incredible, and unlike your gasoline car which wastes 80% of the energy you put into it as heat, electric cars waste only about 10% of the electrons you put into them, and as the electricity grid gets greener, your car does too. A gasoline-powered car is never going to get cleaner or more efficient over time. Electricity is also much cheaper… since December, I’ve driven 6850 miles at a cost to me of about $35 (Nissan makes a bunch of public chargers available for free for two years, but I usually charge at home). In my Camry, 6850 miles would have cost over $1300 with gas at around $3.50 (I’m guessing at that price, I haven’t been to a gas station since December)! Even if you include the $170 in train tickets that I bought for a recent trip to Portland with the kids, instead of driving Lolly LEAF, I’m still massively ahead financially… oh, and the Camry would have needed a $40 oil change about now too…..
    Happy Motoring (as AAA used to say)

    • You really know your cars! Thanks for this information.

      So here’s the challenge for me with electric cars. I work from home, so I rarely drive at all. Maybe a few times a week at most, just to run errands. So it would seem that an electric car would be ideal.

      However, I live in a condo, so there’s no place to plug in the car. Also, 1-2 times a year I drive home to Virginia. I could rent a car for that purpose, but it triples the cost of the trip if I have to do that.

      Perhaps someday an electric car (or fuel cell) will be a great fit for me, and I certainly look forward to that day. 🙂


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