PLEASE HELP!! P0300 code

[prburner]

my 2000 celica gt throws a p0300, which is random multiple cylinder misfire
symptoms: jumpy idle, very rough idle, bad throttle response

if i unplugged my cam position sensor and nothing changed as far as engine performance, could that be the cause?

[iToaster]

I doubt the cam position sensor has much to do with this, although it can cause this code. The rough running tells me that you're having ignition problems, I would check that the spark plugs are ok first, then move on to the rest of the ignition system. If everything is in check there, it could be an issue with the fuel system.

[Bitter]

Clean the Mass Airflow Sensor.

[prburner]

well, i found out that the fuel system is working correctly. i had pulled the plug on each injector one at a time while running and i ran much rougher.
since its a RANDOM multiple cylinder misfire, a mechanic said the timing is probably off. does anyone agree?

[iToaster]

The timing could be off, but I think it is unlikely considering the engine uses a timing chain and coil pack ignition. How long has it been since you replaced the spark plugs? I'd pull them out and check for buildup if I were you. If the plugs are new, they could be improperly gapped. Bitter's suggestion has merit as well, a dirty MAF can cause a lot of problems due to unmetered air entering the engine. A $5 can of electronics cleaner from Radioshack and two screws is all it takes to clean it.