What is the worst song to listen to in the car because of sirens wailing, brakes screeching, horns honking, or any other scary stuff?

Not quite what you're asking, but I once fell asleep on a long haul flight listening to a Cinematic Orchestra album with some very comfy headphones.

I woke up to a little filler / ambient track that is mostly silence with a ship's fog horn blown a few times... The cabin was dark, most people were asleep or quietly watching movies, and my half asleep brain forgot I was wearing headphones. I went from confused to creeping panic about what this horn meant and why no on else was reacting to it until I finally woke up properly

I can't think of a specific song but I can say that I hate when radio ads do that shit.

Time by Pink Floyd.

Back in the day. Moped, cassette Walkman, and very early wired earbuds. The engine noise covered the several minutes of ticking in the beginning, so it seemed like the tape had stopped. Then the alarm clocks kicked in and startled me so badly that I almost crashed.

Anything by Skrillex.

Not an answer but noticing you username and the question do not go together at all threw me there, respect

Not the worst but has horns and tires screeching: “Toxygene” by The Orb

Anything by Blippi, but in particular, the police car and firetruck songs

Not really a music track I can suggest, but I have a small story to share...

Many years ago I got interested in number stations, annonymous shortwave radio stations only transmitting an identifier and series of messages encrypted and converted to numbers, these messages are instructions to spies in foreign countries.

The Conet Project is a collection of recorded number stations released in a CD box set.

Right, I was at a LAN party, and was playing some multiplayer OpenTTD and had The Conet Project playing in the background, after several normal number station recordings, I got to a recording that only was a high/low tone on repeat for several minutes, so I zoned out...

Then, suddenly the high/low tone went away and just as I noted it, the sound exploded in random tones just blasting me through my headphones, and I felt as if my brain was being reprogrammed, I yankee off my headphones and realized it was the track playing, and that it was a polytone station, sending data via tones instead of reading numbers.

Last Kiss

My wife added ABBA's Dancing Queen to our driving playlist for our first long trip. Silence into a deafening piano slide half way through the drive was an interesting way to nearly die from shock.

Mr. Ambulance Driver by The Flaming Lips

Somewhat unrelated it should be illegal to put dogs whining, babies crying, and other irritating noises in commercials.

The closest i have is Local H, Bound for the Floor. The staccato distortion throughout makes (to my ears) a sound very similar to a 1992 Ford Tempo's "Your seatbelt isn't latched" chime.

I would be driving like a madman to highschool after oversleeping and it would make me keep double checking my belt.

There are some songs by Elektronomia that sound like the car window is down.

Mashin on the Motorway

Not too scary, but the intro to Tune-Yards’ Gangster makes me reflexively look in the rear-view mirror to see if I need to pull over.

6 O' Clock News by Merkules and Chris Webby always gets me with the horn and siren bit.

Shiver by Fever Ray

Fancy Shoes. Always have to mute the stereo for a few seconds partway through the song

Friends of Mr Cairo