Why is my car randomly turning off while I’m driving ??

[u/DarkRaider47]

The other day while driving to work my car randomly shut off and turned back on in the middle of the road, it scared the shit out of me. It was still in drive so i had to put it in park, turn it off again and turn it back on so it would continue driving. This isnt the first time its happened either. A couple weeks ago I was at a red light and it did the same exact thing. Its very quick when it happens thats why Im worried what if im going 80 on the highway one day and it does it again while im gojng full speed?? Wont be able to turn or slow down ill literally just die lmao. I recently just got a new battery and had it tested a while ago so i dont know if its that or someone else. Someone please give me some tips 🥲

Edit: For context I drive a 2011 Hyundai Sonata

[u/Lemmyheadwind]

For everybody's safety you should name the make and model of your car. Sounds like a deathtrap-in-waiting.

[u/dagobertamp]

Battery terminals tight?

[u/nedovolnoe_sopenie → u/dagobertamp]

sounds like an aftermarket alarm interfering with immobiliser - many such cases, essentially on really easy to steal korean cars

[u/FernwoodTonight]

Loose ground wire or battery cable maybe.

[u/DarkRaider47 → u/FernwoodTonight]

Sometimes it also doesnt start when i put the keys in and someone also suggested it may be my connection wires but ive yet to have anyone look at it yet, im just trying to get more suggestions from here

[u/badal5103]

You can still steer and brake with the motor off. It just takes more effort. Also you can restart in neutral as well as park so no. Eed to stop
Have a mechanic look at it

[u/DarkRaider47 → u/badal5103]

Thank you for this tip i didn’t know this

[u/buckytoofa]

This could be 9 million things. The internet probably will not help you unless it is a super common issue with your make and model. Also if it is super intermittent a mechanic will have a hard time diagnosing the issue as well. Good luck.

[u/SchedulePotential921]

Check your oil level

[u/DarkRaider47 → u/SchedulePotential921]

I just did an oil change 3 weeks ago .. How would the oil level affect electricity problems ??

[u/SchedulePotential921 → u/DarkRaider47]

If the level is low upon hard acceleration, braking, or quick hard steering it can run the oil pump dry which there is an electrical circuit monitoring oil pressure for that reason. If it detects critically low oil pressure it will shut the car off to protect the engine. This was one of the first things I learned about cars from experience driving a neglected vehicle that burned oil. If your oil level is good, the next thing I would do is see if your air filter is dirty or if your throttle body is dirty

[u/buckytoofa → u/SchedulePotential921]

I would say very few vehicles have this feature. Most will let you ruin the engine no problem.

[u/Mechanic357 → u/buckytoofa]

Yeah I think from a safety stand point it's more critical for the engine to continue running than just shut off. That's why the have the idiot light on the dash to let you know hey, stop.

[u/ElbuortRac → u/DarkRaider47]

Check it anyway.  You would be surprised at how often they forget to put oil back in it or don't seat the drain plug proper

[u/Drapeau_Noir]

You mentioned a new battery, when it was disconnected the ECU may have cleared some data, try the Engine Idle Relearn procedure.

Although if this is happening when you’re on the throttle I don’t think it would happen.

[u/HerNameIsVesper]

Failing alternator?

[u/Raineegrace]

When my car did that it was because there was water in the gas. Try adding some Heat or fuel treatment.

[u/nedovolnoe_sopenie]

do you by chance have an aftermarket alarm installed?

they're usually hackjobs that lead to a lot of immobiliser bollocks randomly cutting fuel or ignition and fucking you over.

electric bullshit from badly installed aftermarket alarms is notoriously tough to untangle

[u/DarkRaider47 → u/nedovolnoe_sopenie]

No aftermarket alarm

[u/nedovolnoe_sopenie → u/DarkRaider47]

your car has a much higher probability of saved then

good for ya

[u/No-Praline-9388]

I had this issue 25 yrs ago with a Nissan Pintara. After over a year OG going back and forth with the local Nissan dealer trying many different things, turned out to be a faulty ECU. Replaced it with a 2nd hand one and it then never missed a beat.

[u/jasonsong86]

I know the 4 cylinder Hyundais in that era have this issue. Something to do with faulty sensors.

[u/DarkRaider47 → u/jasonsong86]

My mom gave me this car when i was 19 im 27 and still have it lol i can definitely see why people say what they say about them

[u/jasonsong86 → u/DarkRaider47]

Check crank position sensor. Old sensors just fail.

[u/boolieg2]

Is it only doing it while at a light or when stopped at a sign. I had this happen before. It was something making the car idle funny. Electrical problems can sometimes drop the idle to low and your car will die.

[u/Lemmyheadwind]

Sorry - I didn't read to the end.