FC vert won't stay running, laggy throttle.

my buddy owns a 91 FC that won’t stay running. At first, it had some issues with the TPS so I adjusted that and it seemed to help (the idle settled down). A few months later it started revving to 3k when started then dying after warming up. I’m pretty sure from what I’ve read this is a thermo wax valve or whatever but now the car just won’t stay running at all. When you turn the ignition on the horn just stays on (I assume it’s unrelated but it’s annoying and will need fixed cuz we just pulled the fuse). When I got it running it started, revved to about 3 then wanted to die immediately. I was able to keep it alive by pumping the throttle but there was virtually no throttle response. In the video you can see it almost die. I was giving it gas immediately after the revs start to drop. After it dies it won’t try to start for a bit, then repeats. For now, I was gonna have him buy a thermo wax valve but we kidnapping wanted to get everything at once. Unfortunately I’m not near the car and won’t be for a week so any extra questions may not get a proper answer but I may be leaving something out. Any help will be greatly appreciated.