On the turn signal switch, if one side is not cancelling out. Is something inside that's causing it, fixable?

If you pull off the wheel you can determine what the issue is. Most likely a broken tab.

Check the steering wheel canceling ring as well. It’s on the back of the hub. I’ve had a turn signal switch that appeared intact but did not cancel. It can be tested when the steering wheel is removed. Turn signal left or right and at the three o’clock position force the tab with a small flat blade screwdriver Up Or down

It seems the aftermarket horn ring and tab are too short and I also noticed the turning indicator assembly cancel section does not stick out as far as the stock one. Some people put washers under the horn ring to extend the tab.

Take some photos and show us how you fix it

Me too ..............
When I come up for air after working on other peoples cars. Mine need attention.

I was told:

If it seems sluggish or sticks moving the handle, the screw tension needs adjusting. If it moves freely, it's probably a broken tab on the switch.

Remove the steering wheel. There are 4 cheese head straight blade screws. Get the lever to hang up and loosen/tighten the screws until the handle doesn't drag.

Agreed with @partwerks on the screw adjustment. Those screws need to be just tight enough to hold the switches in place but shouldn't be pulling so hard that the switch bodies are distorted/twisted.

Inspired by @cuddy_k

Turn signal view video

Sorry Ian I didn't add the wheel removal , not worthy

Ha! Great information there!

You may want to change the name of your video to "Porsche 914 turn signal switch overview" or something like that to make it more searchable. Right now it's just called "August 7, 2020"

Nice!

Click to view attachment

All tabs look ok. Loosened the 4 screws a bit, but still drags a bit. I sprayed some contact cleaner in there. Seemed to help, so might use the air hose to blow anything else out?

Seems like it might just be gummed up?

i'd loosen the 4 screws a bit more and wiggle the switch back toward you 1/8-1/4 inch or so if you can. see if that makes the turn signal stop binding. if so...slide it back in and just barely tighten the screws down. blowing out the crud and a little lube can't hurt.

I wonder once I get it cleaned out, if putting some graphite in there would be the right, or the wrong thing to do??
I would assume the turn signal can be separated from the wipers, and maybe cleaned up better?