Hi,

You need to find another mechanic as the ECU in these cars are very reliable. It is the very last thing you want to blame and in this case. He is doing this as he doesn’t have a clue and doesn’t want to work for his money doing troubleshooting.
The faster money is made throwing parts at the problems and getting on to another fish or client on/in line.

How do you know you that the injectors are not working as there are many things that are back down the line that can cause idle issues.
In the first line of troubleshooting the ignition system has to be in great shape to avoid rainy day running problem issues. Moisture monkeys with high voltage big time! Bad wires being number one! Cap rotor and so forth.
Did he replace those already as it’s easy money to pop those off and on!

The computer that takes care of running the injectors and it is on the inside of the car, under the glove box. Unless you have a leaky windshield or wiper motor grommet it shouldn’t be getting wet.

While you are under there, the fuel system relay is there and they are know to fail as it controls the fuel pump and the injector circuits. If it dumps in and out you will go no where!
You did mention getting it back on the road, so you are having start issues and not just idle problems?

Tell us more and you can forget those mechanic leeches!
There are plenty of helpful people around on here and FAQ searches might help you!
Just need to take small steps and learn things. It can be entertaining!
These cars are simple and inexpensive to maintain once you get the low down on what’s what!

Phil