2001 Hyundai Sonata Check Engine Light and Engine Running Bad – Why?

Reader Question Thursday driving my 2001 Hyundai Sonata GLS check engine light is on and car sputters near my home. I take it home and checked & was low on oil. I take my husbands car to go buy oil and put it in. I tell my husband about it, he takes it to nearby store no problems, no check engine light.

Friday I drive it as normal; probably about 30 to 50 miles for the day. No check engine light and no problems.

Saturday ran all day from here to there no check engine light and no problems, then I bring home the family and go out to finish some shopping when on my way home I think I hear sputter again.

Go to turn down radio at which time car sputters again, then jerks check engine light comes on again but I get it home without incident after that. Decided would take it in after the holidays, moved it on Sunday from where it was parked started as normal. Husband said start it every so often. Next time maybe Monday or Tuesday tried to turn over once then after that not much turn over.

This Tuesday jumped it with my husbands car. Was hard to get jumped but finally did. Went out couple hour later started again no problem and check engine light no longer on.

Started Wednesday no check engine light and no problem.

Started today (Thursday) no check engine light and no problem.

Can this be as simple as a bad cell in the battery? I don’t want to put a new battery in if something is draining the battery. What is your opinion of these symptons?

Thanks for your help,
Judy

Hi there Judy,

Thanks for your email. I really think you might have two problems…which was just coincidental. If the battery was original to the car, it was time for a new one. Five years is the MOST I have seen out of the life of a car battery. So you were probably past due there.

The check engine light issue, have you read my article on that? I would suspect you might have an engine “miss” (since you said you felt the engine jerk) from a worn out spark plug or spark plug wire or something along those lines. If the engine has over 50,000 miles I would say have your mechanic check to see if you need a tune up.

If the engine miss-fires (from needing a tune up) the computer onboard will signal the yellow check engine light to come on to indicate a problem has occured. I am assuming you are talking about the yellow light not the RED engine light…correct?

It is perfectly normal for the yellow light to come and go if there is an intermittent running condition, and low oil is usually not something that affects the YELLOW light to come on. That yellow light is like an emission light, it is looking to see if the engine is running at peak efficiency, and not polluting the air with too much exhaust from running poorly.

When an engine miss-fires or “misses” one or more of the cylinders did NOT burn the fuel that was inside the cylinder so that unburned fuel was pushed out the tailpipe which as pollution and your computer noted the problem and set the light to warn you of a potential problem. So, the yellow light is doing its job of reporting a problem with the engine.

The next day you get in your car…and it runs fine…no misfire and no “jerk” is present so no yellow light is seen on the dash. The next time the engine jerks…the light should come back on.

I would start with checking to see if you need a tune up first, and see if the “jerking” and check engine light issue goes away. If not, then have your mechanic dig deeper into what is causing the light to come on, but with intermittent problems like this your mechanic will probably have to catch it in the act to be able to properly diagnose it for you…which might be easier said than done.

Here is that article I mentioned.

Check engine lights

Blessings,

Austin C. Davis

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