1994 volkwagen golf, only starts when starter fluid sprayed into air intake. After starts runs fine. after warmed up, still doesn't start without fluid

no
you fix the reason why the injectors are not working
could be fuel pump , pressure regulator , injectors , wiring or ECM
have the fault codes read

Do you have normal fuel pressure when you first crank it ?

bypass the starter motor, see the diagrams attached, and see what happen, you will have a new vision with this.
God bless you

could need tuneup and may want to replace fuel filter....Thing i would do first....i hate starter fluid...really ******* rings in motor.....

Many cars nowadays have sensors built in to make then run economically and reduce pollution. If you start you car for very short runs, after a while these sensors become fouled, and/or they shut down to protect the engine.

Without diagnostics, I can't say exactly what the problem is but, I would suggest the next time you start the car, you give it a good run and get the engine good and hot to burn of any deposits stuck inside. (about 40 miles). Assuming this works, give you car a good run, 20 minutes, at least once a week.

starting fluid is a thing of the past. dont use it. this car doesnt have a carb, its a throttle body/ electronic fuel injection system. you most likely have a fuel pump or fuel pressure regulator issue. test the fuel pressure, should be anywheres from 35-50 psi

there is a large tube that goes to your throttle body (you do not have a carb), remove it and spray there-be careful, starter fluid is highly explosive, spray 2 or 3 short bursts into the top of the throttle body opening, and install the tube (you don't have to tighten the clamp). You may have to repeat this a few times, if you can only get the car to run for a few seconds 3 or 4 times, and it will not run on it's own, you have a fuel delivery problem, and no amount of starter fluid is going to fix it.

sounds like the fuel pump is going out. next time it won't start have the fuel pressure tested or spray starting fluid into the air intake to see if it starts.

With the vehicle turned off: spray some starter fluid into your intake. You'll have to take off the hose from your air filter assembly to do this. After you spray some starter fluid reinstall the hose to your intake. And try to start your vehicle. If it starts every time you do this and runs without issues. Then you could have a clogged fuel filter or the fuel pump is going out.

Well, obviously someone didn't tell you the truth because spraying into intake doesn't make the vehicle turn over any better. You have ignition or fuel delivery problem. Start by taking fuel line off at intake and crank engine a couple times catching any gas in a cup or something. If none, then trace fuel line back and under vehicle til you find filter. Should be under driverside midway back on inside of frame. Change this and try test again. If no gas, see if fuel pump is on motor(mechanical pump). Change this and test again. If not on motor then it's in gas tank(electric pump). Most cases the tank has to be lowered to take out pump, careful not to drop, dent or make sparks. Some came with access through the floor so check that first. Normally you can hear an electric pump come on when you turn the key. Good Luck