My car recently quit cranking. I don't know what caused it. It was hard to start one time, and the next time it wouldn't start at all. Now it's broken down at my college and I don't know what to do. It tries to turn over. It makes the rarrarrarar noise but it will not start. I have heard that it's the fuel pump, the coil pack, or the ecu. Please let me know what it could be and what I need to do in order to narrow it down. I have already checked the plugs and the battery is new.

So it cranks but does not turnover?
Check the coilpack then

Get some starting fluid and spray it into the air intake duct. Then crank the motor. If it seems to stumble like it wants to crank, it may be fuel related (eg fuel pump not working, no gas, fuel pump relay,etc.) Keep in mind the fuel pump may not be working because it is not getting electricity. If there is no difference, it is something electrical. ( eg no spark due to coil, spark plugs, ignition module, or no elec to fuel pump, bad fuel pump relay. ) Bottom line, if it stumbles after using starting fluid, check for current at the fuel pump electrical connector. If there's current, bad fuel pump. If not, check fuel pump relay and/ or wiring in fuel pump circuit. If there's no difference, check for ignition spark.

...Do basic troubleshooting.
By the way, cranking IS turning over.

Do you have spark? crank it with the plug grounded on the head. Are you getting fuel? Spray starting fluid into the TB. Do you have compression? Do a compression test.

If you turn your ignition on but not start the car you should be able to hear the fuel pump, but i had a problem like that last summer and it was the coil pack.

I have already checked the plugs and the battery is new.

so did the plugs have spark? if so that narrows it down to either fuel or compression... also you might want to check the fuel filter while your doing your little tune up and checking on things! does the fuel pump turn on when you turn your key to the on position? if so, check the injecters, they might be pluged! there are so many possibilities that i can think of right now... you need to also help us narrow it down too by updating us on what you are tring, let us know!

Thanks got a big test coming up. I'll try all of that thursday or friday. Thanks sooooo much for all of you help. I really appreciate everything that you've told me. I'll keep you posted on what i try.