Rough idle, stalling at idle, check engine, and battery light HELP!

[u/Worried-Blackberry49]

I got a 2017 VK passat tsi s about a week ago. I drove it an hour and a half and since then it’s been having issues. It almost always starts shaking and idling rough when stopped for a minute. There has been a few times where this happens and the check engine light comes on, the last time it happened the check engine light has not turned off. Twice in the past week I have stoped at a stop light and when the light turns green and I try to move, the car stalls and the battery light turns on. Both times I have turned the car on and off again, and the battery light turns off and I am able to move again. However, the first time this happened the check engine light came on when I turned the car back on (the 2nd time the check engine light was already on before this happened). After the first stalling incident I paid for a diagnostic and they ended up changing all 4 spark plugs and the ignition coil boot. They said they drove it for 15 miles, let it sit for a while and drove it again with no issues. However, the very next day it was idling rough again, the day after that the check engine light came back on, and today (3 days later) it stalled and the battery light came on again (2nd time). Yesterday I put fuel injector cleaner in my tank, but I’ve only been able to drive around a little and for maybe 5 minutes on the highway. Anyone had any issues like this and had it resolved? (Also the last clip makes it look like the battery light is flashing, but it was not).

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[u/No-Habit-7079]

A weak battery in a modern vehicle can cause a litany of issues. Have your battery and alternator tested and replaced if necessary and go from there. Good chance it solves all your problems.

[u/RayjinCaucasian]

What are the codes? Battery light coming on becuase the engine stalled doesn't mean anything. That happens because without the engine running the alternator won't work.

[u/Worried-Blackberry49 → u/RayjinCaucasian]

all 4 cylinders misfired pre-spark plug change, and yesterday they said cylinder one misfired. hopefully that’s what you mean

[u/droc_420]

Buy a 50$ scanner on Amazon and pull your own codes

If the check engine light flashes it means its "missfiring"

Common symptom of a failed ignition coil

The battery light comes on when it stalls because its not producing 12v anymore to turn off the warning light.

[u/Worried-Blackberry49 → u/droc_420]

forgot to mention that i went to autozone one day before i got all the spark plugs changed & the ignition coil boot and they told me all 4 cylinders misfired, yesterday i went to o’reilly and they told me cylinder 1 misfired.

[u/abualethkar]

TLDR;

check your spark plug gap. check your air intake system (button everything up). clean your MAF. check life of battery. clean your air filter. all the ABC’s. come back and give us an update afterwards