Diagnose engine misfire problem

I am so disappointed right now.

Just feel disgusting some how in my stomach. I am sorry for saying this.

I just replace 3 fuel injectors, for cylinders 1, 3, and 5.

Same problem!

The replace and hope method just doesn't cut it.

There has to be a way to test these things the right way.

This is a very funky problem. I took it to an auto service center. They have been looking into it for 3 hours, and haven't figured it out. They have changed the sparks and wires. Also test pressure again and they said there's signal in the fuel injector electric wire. I'll update if they find anything, or any news on this.

I am sorry for the last post. It was a moment of frustration. I didn't mean to aim that at anyone. You're all been very nice and helpful.

So, I took it to a Chrysler dealer. Initially, they asked for $100 to look at the engine problem. Later, ask $250 to open it up and look inside. They still can't find out the problem. They suggested to open more (cylinder head, or something like that) for $400 or replace the engine for $3600 (with 3 years warranty). They also mentioned of the cost of rebuilding would be $2500 with 1 year warranty. That's after 4 days of looking into it. I paid them $250 and took the car home.

I took it to a mechanic that I know, couple hundred miles away. He said the knock appears to come from a cam that developed a hole in it (due to some manufacture defects). He replaced the engine. He said he opened it up and it was the problem.

The car runs fine now. I wonder if that problem can be fixed or replaced locally to lower the cost instead of replacing the whole engine. Anyone familiar with this mind to share?