2011 Sonata Engine Stalls When Sitting at Traffic Light

ethandouethandou Member Posts: 15
I posted this problem before. But this happened again. Here’s the story.

My Sonata was purchased in March 2010. Within one month, the engine stalled when braking to a full stop at traffic light. I took my car to the dealership. They couldn't reproduce the problem and just refreshed the computer software. A little over one month later, my car cut off again while sitting at traffic light. Maybe another one or two months later, it happened the third time. I had my car towed to the dealer that time. They kept it for two weeks but still had no clue. Weeks later I did the first oil change which seemed to help a bit. No stalling occurred after the first oil change and another oil change. Until recently the problem came back again. One day, when it sat at traffic light, the car shook a little like someone hit me. I looked around and no car was close to mine. The other day, this hit-like shake happened again while at traffic light. This time, the car even shook several times during driving after leaving that traffic light, with the check engine light blinking in accordance with the shake. Yesterday, my car finally stalled again at a traffic light.

Except the first one, all other occurrences happened while the car sat at traffic light and I stepped on the brake pedal. After I restarted the car, it could run smoothly for at least one month. I even bought a cam to record the dash while driving. Since the problem seemed gone away after oil change, I stopped recording long time ago.

Given the occurrence frequency, the chance to reproduce the problem at dealership is close to zero. And they refused to lend me their computer that could hook up in car to record driving data. I had also contacted Hyundai Customer Affairs before. All they can do was just send me to the dealer and close the ticket. Any suggestions, folks? This is really disappointing and embarrassing when cars behind me watch me restart a Sonata new model.


  • targettuningtargettuning Member Posts: 1,371
    Well, as you yourself stated it is such a random occurrance that the chances are slim it will reappear on demand at the dealer but there is a brake interlock switch that allows the engine to be started in the first place and as you know one must depress the brake pedal to start the car. Since this occurrs when you have your foot on the brake maybe this is related to that interlock switch. I have read accounts of those switches failing thereby not allowing the car to be started but maybe this is a variation of that issue?
  • ethandouethandou Member Posts: 15
    Thanks for your reply. I'll ask about this when I go to dealer next time.
  • ephraim1222ephraim1222 Member Posts: 1
    It could just be that the air flow sensor is blocked. It's a very easy fix, I had the same problem with my 2000 SS Monte Carlo. Just ask the guys at Auto Zone and they should be able to tell you where its at. When I had the problem my RPM's would fluctuate at a stop light before failure do you have that problem too?
  • ethandouethandou Member Posts: 15
    The RPM is quite staple at a stop. Based on my previous experiences, all were like unplugging power supply.
  • daysf1daysf1 Member Posts: 1
    There is a throttle cut off on your Sonata that will cut the fuel supply to the engine if the brake is applied while still having your foot on the gas pedal (can only be done if you drive with both feet, one on gas other on brake, or you have REALLY wide feet). Have heard of this happening when stopped on a hill as people are afraid of drifting backwards, or there are alot of people that do drive with both feet (racecar drivers). This is a safety feature designed in response to a certain car company dealing with reports of runaway car that were unstoppable even with both feet applied to the brake (Toyota). Toyota claimed it was floor mats getting stuck and not releasing the gas pedal. By utilizing this safety feature, Hyundai has eliminated this as ever being a possibility on their vehicles. It is on most of their newer vehicles now and will be on all other models beginning in may. This will also be a federally mandated safety feature i n the near future, as Hyundai usually does these kinds of things long before other manufacturers or even the government steps in as was the case with standard stability control across the entire Hyundai lineup. Not sure if you fall into this category but either way you now know of a safty feature on your Hyundai that you probably didnt know you had.
  • jay_kayjay_kay Member Posts: 1
    I've had my '11 Sonata Limited for 2 years now. I just discovered this discussion today. The car has just over 20,000 miles and twice it has left me stranded, when it won't start because of the brake switch problem. Both times it had to be towed into the dealer and the switch replaced. I have also experienced the shudder while sitting at a stoplight. I haven't actually had the engine stop, but on maybe up to 6 occasions -- and to varying degrees -- I have had the car shake. The first time was the worst and, like I read here, I thought someone in traffic had hit my car and instinctively looked around to find the culprit .... but there was none. I really hate this car ....... and my experiences with the dealer are approx. 20X worse than the car. How this dealer is allowed to operate under a Hyundai sign is disgraceful.
  • larrys1352larrys1352 Member Posts: 11
    I have a 2012 Sonata Limited that I bought in November 2011. Since we're retired we don't drive too much and the car has less than 7,000 miles after a year.
    My problem is that several times a month, when I hit the gas quickly to enter traffic the car almost dies...it never does die...it drops to 0 mph and then in 1-3 seconds it accelerates. I am really concerned about getting braod-sided some day.
    I mentioned this to the service department but of course they could not replicate.
    Does anyone else have this issue? Any ideas?
  • normandy2normandy2 Member Posts: 3
    I have purchased a 2013 Hyundai Tucson Limited and it now has 4000 miles on it.
    Yesterday while making a left hand turn the same thing happend to me.
    I almost got broadsided by oncoming traffic. The same thing happend to me this morning.
    I haven't brought the car into the dealer yet and I hesitate to give it to them if they keep it for a week and then tell me than can find nothing wrong with the car.
    I also have a 2009 Hyundai Sonata with 30000 miles and have not had any problems.
    I am about to get rid of the car and buy a different make and model.
    Any info will be appreciated.
  • larrys1352larrys1352 Member Posts: 11
    I found my answer and maybe this will help you. Many years ago I worked in Northern NJ but lived in South jersey. During the summer I would be in bumper to bumper taffic for hours so I started driving with 2 feet, I still drive with 2 feet. I read somewhere on these Edmunds blog that if you hit the gas and brake at the same time...even for a second...the engine will "almost" stall.
    So I focused on that and sure enough the problem went away.
    Maybe this will help you.
  • normandy2normandy2 Member Posts: 3
    Thanks Larry,
    I read the same item about pressing the brake while pressing the the accelerator. The article I read states that Hyundai put in a switch on the break pedal to cut off gas supply to the engine if you press the break while accelerating. Has to do with the problem Toyota had with run away cars.
    I read that the feds will be making this manditory on all cars.
    Hyundai just beat them to it.
    I don't understand why Hyundai doesn't make this info available to there dealerships so they can pass it on to their customers.
    It could save someones life.
    By the way, I started driving with one foot and the problem went away.
    Thanks again for your reply.
  • kb9oaukb9oau Member Posts: 1
    Just drove my 2011 sonata off the lot 4 days ago, purchased used with 77K on the odometer, no problems until I filled the tank and drove 500ft and parked and shut down the engine waiting for my brother for 5mins. Tried to start and the starter did as it should but the engine just sputtered enough to disengage the started just reaching 1K on the tack. Tried many many times and same response. Still sitting on Kroger parking lot. Any one else have a similar problem?
  • gwjugwju Member Posts: 1
    Hi; I have a 2011 SONATA LIMITED and it has just started doing a similar thing-personally I find it kind of scary and will be visiting the dealer shortly to have it checked- meanwhile did you ever resolve your issue with stalling. My car has about 25000 miles on it.
  • normandy2normandy2 Member Posts: 3
    I had the same problem with my 2013 Tucson Limited.
    I resolved the problem, no thanks to Hyundai and its dealers.
    It seems that Hyundai, in response to the problem Toyata had with its accelerator sticking, installed a "switch" or some other device to cut off the fuel supply to the engine if the brake is being applied while the accelerator is pressed.
    Thanks to a previous message from a member he told me the cure.
    I was driving, as he was, with my right foot on the accelerator and my left foot on the brake. DON'T DO THIS.
    After adjusting my driving habits the problem is resolved. No more stalling.
    The Hyundai service department is clueless to this.
    Try it. It fixed my problem and I hope it fixes yours.
    Norm - Elkhorn,Nebraska
Sign In or Register to comment.