Good luck. Fuel injectors on most vehicles are at least $100 a pop, not to mention you have to rely on a computer to handle all sorts of things in the background.
I'm a fan of Ford/Autolite/Motorcraft carburetors. Many say the Motorcraft 2100 is the greatest carburetor ever built. You can completely rebuild the thing with a $20 kit from Autozone and it takes about 15 minutes. You can make adjustments with just a simple screw driver.
When EFI goes bad it could be anything. I had dirty fuel injectors a few weeks ago. I got lucky and managed to clean them with just a Techron treatment. It could have been a lot more costly.
So far so good with this cheap little car, but like I said, I do prefer carburetors.
EFI does have its advantages though. For one, when things are working correctly, you are pretty much guaranteed to have a perfect mixture of fuel and air. With carburetors, you have to do a little bit of tinkering to get it just right.