Car misfires and the CEL blinks?

The car can be driven but it has no power and misses.
A diagnostic tool said "cylinder 2 miss fire". A friend who is a mechanic messed with it and says the 2 and 3 cylinders are firing at the same time.
I changed the coil, plug wires, plugs, air filter, oil, oil filter, fuel filter, air intake sensor, and checked the fuel line to see if it was clogged and checked the injectors but didn't replace them. I'm getting desperate and running out of money, any suggestions?

Its a 2.2L and its getting spark at the plug. I assume we checked the fuel pressure, but I think the problem is something else. We decided to hook up a timing light to it just to see if that could tell us something and it looked like there isn't a constant spark, like it will flash constant and pause for half a second at odd times like its skipping a spark every once in a while, but we didn't know if it was supposed to do that or not. One thing I forgot to mention is the "Trac" light comes on when it starts missing and when it goes off its fine. Its on more than its off. When you drive it, it will be missing then it will start running fine for about 5 minutes, then runs bad and then good over and over. The check engine light sometimes comes on, but usually only if we are driving it for 10 minutes or more. I guess I will probably have to take it to a garage and let them do some tests on it

My car is missing intermittently. When it does this, the check engine light comes on steady until the car shifts into drive when it starts to blink. We have replaced plugs, wire, and coils. When it did this in the past, it coded for a misfire on cylinder 4. What could it be?

The engin was presure washed and now the car is skipping. Also the Check engin light and the Track Off light is on.

I have a 2000 Chevy Cavalier 2.2L which was recently diagnosed as having a cracked cylinder head as the reason for a bad misfire. From the mechanic's own words, radiator fluid had been leaking into the cylinder, but my radiator fluid levels are fine, there's none of the typical smell of antifreeze after driving the car, and it hasn't had any engine temp problems in a while, despite driving around with the misfire for over a month or so now. They already charged me $700 for electrical work that they first 'diagnosed' as the problem. Could this be the real reason, or is my mechanic just trying to bilk me out of even more money?