Car wont rev past 2500rpm

Sounds like a low fuel pressure issue or a stuck open egr valve/air leak.

1. replaced the air filter
2. replaced the PCV valve
3. inspected the PCV hose and connectors (nothing wrong)
4. ran a tank of gas with fuel injector cleaner
5. tested the EGR valve by pulling the vacuum hose off the top, and blocking the hose. The idle didn't smooth out. I applied a vacuum to the EGR valve manually and the car immediately stalled which tells me that the EGR valve itself is working fine.

Did you test any of those parts before you replaced them ?
Have you checked the cap, coil, and distributor yet ?
The distributor has a module and a pickup coil inside that could be faulty.
Is the check engine light on ?

SOUND LIKE FAULTY IDLE AIR CONTROL MOTOR.TAKE VECHICLE TO GARAGE LET THEM SCAN VECHICLE.IF IDLE SPEED CONTROL FAULTY.IT HAS TO BE REPLACED AND REPROGRAMMED.

When it revs high, is it down shifting? if so you may be running out of gas. low fuel pressure or lack of fuel getting to the injectors. (fuel filter)

fuel presure been checked with gage?

check the vacuum line and map sensor

With the age of the vehical it might be a good idea to do a compression test first. I would check the timing. Sounds like the engine is advancing for some reason, if that checks out then recheck for vacuum leaks( it could be leaking past the base gasket, vacuum booster, or intake), The vehicle has a carb. not a throttle body injection? Also if you can retrieve that engine code it may be helpful.

Faulty coil (pack)

Faulty camshaft position sensor

fuel filter and fuel

the p0300 car's computer has detected that one of the engine's cylinders is not firing p0301 In this case it's cylinder #1.p0302 In this case it's cylinder #2.and so on i would check the three listed above first then check

Faulty spark plugs or wires

Faulty oxygen sensor(s)

Faulty or plugged fuel injector

Burned exhaust valve

Faulty catalytic converter(s)

Stuck/blocked EGR valve

Defective computer Random misfires that jumps around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak that may be a broken hose or in the intake manifold (gasket,spary aruond it with wd40 or starer fluid if the engine idle goes high theres your problem) or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open. hope this helps

If the cat is red then it is probably plugged if the motor can't exhale it wont run at high rpm