crank but doesnt start
 

ok. i drove the car all was well. got in it the next day it will crank but doesnt start. changed the icm, coil packs, plugs an plug wires all new.
still doesnt start. every now an then it will hit but doesnt start. fuel pump runs. get gas. security system is fine.
any ideas as to what could be going on.??

Over the years, I have learned, "fuel pump running" and "getting fuel" is not the same thing. You can have a fuel pump make that expected "hum" when it starts and still have a fuel delivery issue.
- Pump may have failed internally and unable to deliver proper pressure.
- Pump connection in the tank may be bad and never supplying fuel to the fuel lines.
- Could be a kinked line.
Before I settle on "it has fuel", I would find the test port on the fuel rail (normally has a little twist off cover to protect the schrader valve). With the car off (and no attempts to start it), remove the schrader cover, us a small screw driver to push in and open the schrader valve (be prepared, if it has fuel and fuel pressure should be a quick squirt of fuel). If you have NO fuel, you have a fuel deliver problem. If you have a squirt, you may want to put a fuel pressure gauge on it and test further.

ok today i checked it as you suggested. has plenty of fuel pressure.
but still no start. i checked the plugs an they look good/.

Even though you replaced all the ignition stuff (ICM, coils, wires, plugs), I still feel the next step is confirming you have actual spark. There are a few ways you can do this. I recommend either use of a timing light, or a better option for this (as it might also give you visual to a "weak" spark), get an inline spark tester (it plugs between the coil and the wire or the spark plug and the wire). Harbor Freight sells them pretty cheap. I used one and found all cylinders had spark on a car BUT one had a weak spark (as the light did not shine as bright as the others).

Also, what year and engine does your Monte have?

i have a 2003 monte carlo ss. 3.8
im not sure if its getting spark.
as i cant crank it an check the spark by myself

Grab a friend or family member to crank the car while checking for spark.