Car won't keep idle

[DSVW]

Hi,

I have a 1991 Toyota Corolla 1.6 

It has been taken to 2 Mechanics and neither could get it running, both gave up on it. The engine would turn over strong, but just wouldn't start.

I decided to work on it and here is what I did:

New fuel injectors and injector connectors

New PCV valve and grommet, valve cover gasket and grommets

New wires, plugs, cap, rotor, coil and entire distributor

New Throttle position sensor

Tested MAP sensor - it is good

Changed out the computer with one that was tested to work

Set timing to 10 degrees

It does not throw any codes

I can now start the car and drive it, up to about 45 mph before it starts to jerk and eventually it will stall when it warms up

AIR-Air filter is clean, I cleaned the throttle body. I also can not find any vacuum leaks, I sprayed everywhere and inspected every hose.

Fuel-I have every reason to believe filter, pump and pressure are good. I can jump and hear the fuel pump turn on. When I was replacing the injectors the key was mistakenly turned and fuel sprayed out from the fuel rail very strong. Also at near highway speeds it idles beautifully and is strong from the start after stopping at a stop sign.

Spark - Plugs, wires, entire distributor have been replaced. Getting a very strong spark. A prior mechanic replaced the coil and the 2nd one put a whole distributor in out of a junkyard. I decided to buy and put in a whole new distributor with all new parts (It actually started for the first time after I replaced the injectors and distributor). 

Car will start up immediately after sitting for a week. As soon as it warms up or if I start to drive immediately, it will eventually stall.

Any ideas??? I was thinking about taking out the Idle air valve and cleaning it.

Not sure what to do next. It only has 140K on it.