The car seemed to be running on 3cylinders and then the check engine light came on.
Where can I find the oxygen sensor on my 2001 Ford Escort? on 2001 Ford Escort
You need to have the engine light checked and advise to codes on computer. Take for free check at your local autozone and post. You've got 2 oxygen sensors on that one. One in front just down from exhaust manifold and other just pass converter. If problem with them- code will confirm but sounds like misfire.
P0320 is the code; car will not start now; turns over but does not start
Your p0320 code looks like coming back on no power to your igition coil. Does motor seem to turn over any faster than it normally does- if so your timing belt may have broken (hope not cuz could have caused more damage). If sounds like normal turn over could be problem with either camshaft or crankshaft position sensors. Luckily both these parts fairly inexpensive at your local autoparts store and not difficult to replace. I'd start with cam sensor first and then crank.
Replaced the camshaft sensor, coil pack and checked the fuel to fuel rail, checked timing belt and pulled plug and checked for spark; Getting spark-can it still be crankshaft sensor?
Probably not if your getting spark. Not sure why were getting spark if were getting that code. You try some starting fluid to see if briefly starts? If does maybe a problem with fuel pump.