PO340 code loosing my mind! Help!

This is the code that comes up on my 2002 2.2 Cavalier. Camshaft sensor bank 1. After a lot of research I was led to believe it was most likely the upstream 02 sensor. Replaced it, engine light still on. Wipe codes, light goes off, turn off car, turn back on, light back on. What other possible problems could be causing the light to be on? It's been on the entire time I've had the car which is 3 years. I've had it e tested with the light on and it's passed with flying colors. It's up for an e test, actually I have 5 flipping days to figure this out, have it e tested and get a sticker for it. I've been trying to figure it out for well over a month since I realized an e test was due and they've changed the way they do the tests now, they told me even tho the light most likely has nothing to do with the emissions they can't test it if the light is on period. I was told to start pulling fuses because it could be something as simple as a bad fuse. The car is in relatively good shape under the hood, no major problems and much of the car is still factory. No weird symptoms other then sometimes it will rev high at idle or low speed but as soon as I get to 4th gear it always balances out. Anyways, any help is appreciated to try and figure this out.

I Found this online, don't know why I haven't before (found this particular site) but according to it, it says reasons for this particular code. Are these the only reasons? I really just want to narrow it down before I start pulling wires etc.

- Faulty Camshaft Position Sensor
- Camshaft Position Sensor harness is open or shorted
- Camshaft Position Sensor circuit poor electrical connection
- Faulty starter motor
- Starting system circuit
- Dead (Weak) battery

Possible causes include:

Bad ICM or circuit wiring
Bad #1 or #3 ignition coil
Bad ignition switch
Open/short in wiring between ignition switch and ICM
Bad crankshaft postion sensor
bad #2 or #4 ignition coil

You'll need a scanner with live data and testing capabilities to determine which system is at fault. Or pay an hours labor to a shop for the diagnostics. Then you can get it done or repair it yourself. Replacing each part, one at a time is like throwing darts at a dartboard. Hit or miss... and can run you alot more $$.

When you say scanner what type of scanner and where would I get one? You don't mean a obd reader right? Cause I have one of those and it just seems to give me the Po code, I'm not sure if it's live data capable but it was an expensive system, 200.00 roughly.

Funny thing happened, I went to the junk yard to pull a Camshaft sensor, ran into this guy who tells me he's a mechanic and he has a shop 20 or so minutes away and he would test it and tell me if it was the cs itself, so I took it out, 24 hours later new camshaft sensor installed, engine light out and scanner said ready for e test, she passed with flying colors! Only cost me 40.00.