Apple - MacBook Pro 15" Touch Bar running hot

The normal operating temperature range for silicon is much higher than is comfortable to the touch. The heatsinks & fans are directly below the top of the keyboard along the hinge opening. I too have found the upper edge of my MBP to be uncomfortable to touch -- typically when I'm debugging using the F() keys.

My recommendation would be to use a product that allows you to manually adjust the fan speed in order to run the fan at a higher-than-minimally-necessary speed to lower the temperatures accordingly.

I personally use iStat Menus. In that tool, under 'sensors' is a button to 'Edit Fan Rules'.

Incorporating feedback from the OP to create a more comprehensive answer:

Alternatively, if you believe you may have a hardware issue, a trip to the Apple store might be warranted. The OP had a hardware issue that, while mitigated by the iStatMenus approach, really required a hardware solution, including multiple trips to the Apple store, to ultimately resolve.

The first things I would do are to reset both the NVRAM and SMC. Follow the steps below.

Reset the NVRAM

IMPORTANT: The steps for resetting the NVRAM are different for the Late-2016 MacBook Pro models (i.e. different to all other Macs).

For all Late-2016 MacBook Pro models (with and without Touch Bar) follow these steps:

1. Shut down your machine. Yes, a full shut down, not just logging out.
2. Press the power button and then immediately press the commandoptionpr keys.
3. Keep these keys pressed down for at least 20 seconds!
4. Let go of the keys and let your Mac reboot normally.

Note: When you log back in you may need to readjust some of your system preferences (e.g. speaker volume, screen resolution, startup disk selection, time zone information, etc).

Reset the SMC

You should also try resetting the SMC. To do this on your MBP, follow these steps:

1. Shut down your computer
2. Keep the power cable plugged in.
3. Press at the same time shiftoptioncontrol (on the left side of the keyboard) and the power button
4. Let go
5. Turn your computer back on with the power button.

How does your temperature compare?

Once you've reset both the NVRAM and SMC, your MBP should behave how Apple intended. If you still experience temperatures of 88º C and are concerned by this, you can use this resource (which can be filtered) to compare temperature readings with other users. Of course, I'm not sure how many users with Late-2016 MBPs have recorded their temperatures yet.

However, my earlier MBP temp is regularly at 81º C and it performs very well!

Do you have a problem?

Another thing you can do is run Apple Hardware Diagnostics to see if it finds any errors. To do this:

1. Fully shut down your MBP
2. Restart your MBP
3. Immediately press the D key and keep it down until you see the Diagnostics screen appear
4. Wait for Diagnostics to finish (this typically only takes a few minutes)
5. Once complete, one of two things will appear on the screen:
   • a No issues found message
   • a brief description of any errors found plus further instructions
6. If the diagnostics test does find errors, take a note of what they are

Note: If pressing and holding the D key at Step 3 doesn't work, start again at Step 1 and, at Step 3 press and hold both the OptionD keys instead. This will try and run diagnostics from the internet instead, so you will need to allow more time for it to complete.

Let us know how you go.