Is there a way to enable Hotspot when connected to a specific Bluetooth source? I'd like to enable hotspot when my phone connects to the bluetooth in my car (basically turn it on when I start my car).

It would be nice if there was a way to do this in Android 8.0 (Pixel XL), but i'll assume that isn't possible.

Couldn't find a way to do it in IFTTT. Is there another third party app that will let me do this?

I'm not against coding my own script to do this, but I get the feeling that attempting this on a non-rooted device will be quite difficult (if not impossible).

Any suggestions are appreciated!
You can use Tasker to accomplish this

Profile (or Trigger)

Create a Profile which allows triggering of the Tasker upon bluetooth connection:


Go to Profiles Tab and click the "+"
State ➡  Net ➡ BT Connected [Name : Name of your car BT, Address: MAC of your Car BT)
Tap back to exit from this window


Task

You will notice as soon exit, you will be prompted to link this to a Task


Scroll all the way up the Task list select "New Task + "
You can name this Task AutoTethering or anything or leave optionally as anonymous task.
Click "+" to add new Action
Net ➡ WiFi Tether (Set On)


Explanation: When Tasker detects the device is connected to another device(car) via bluetooth, it will run a task that activates wi-fi tether.

This should work cheers.