Rough idle how do i check the idle air control valve on my 95 geo prizm to verify that it needs to be replaced and if that is the problem how do i clear the computer code?

Idle speed or RPM.
old post.
the hot idle on all modern EFI engines
is not set by you ever, it he computer brains job(by EPA laws)
cold idle. is controlled by thermal direct air valves on older EFI.
the Prizm (with a Z) is a Toyota Corolla with sheep skins (GEO)
made same day in the same factory. same parts 99%
a better questions, is tell symptoms first and ask why they happen. 10x better. that.
Idle controls are one of many electronic servo's in the cars ECU/PCM brain, just 1, of many.
read the ASE books on EFI. this is covered there.

new spark plugs this decade. (a tune up?0
the filter is part of all 60k tuneups. letting it clog wrecks good pumps.
my wild guess, its lack of fuel flow, do to old filter.
or low fuel pressure.
car is identical to a Corolla. so is not unique or rare as some Geo cars are.
the cam belt not changes, invites valve kissing piston tops. BOOM
end of engine. (costs more to fix then worth of car)
the word is bogging, my engine bogs
if if bogs WOT (wide open throttle) and dont catch up < ITS NOT THE TPS. ever.
tps bad causes short bogs, called hesitations.
The map sensor , is what measure air flow and the ECU matches fuel to this air flow.
my guess, is it does that, but fuel pressure is like 15PSI, bad.

Check for loose vacuum hoses or loose wiring. The issue could be electrical in nature or from the vacuum hoses. If you experience rough idling before it stalls then your idle air control valve may be dirty or is faulty.

Sounds like your Idle Air Control valve is bad. The IAC valve controls the engine idle speed. The valve is located on the side of the throttle body. This valve allows the necessary amount of air, as determined by the (PCM) and controlled by a duty cycle signal, to bypass the throttle plate in order to maintain the proper idle speed. Good luck!

either the throttle position sensor is bad or the idle control valve is bad-they can be removed and checked with a digital meter or just cleaned/replaced

Yes it is, will bent cylinder head valve's, timing belt replacement every 60,000 miles.

The problem is in the idle air control valve which controls the idle of the motor and idles the motor up when an extra load is put on the motor. It is mounted on the throttle body and is a little round barrel looking item with a plug in on the end of it. change this part out and clear the engine code in the computer and it should fix the issue.

rough idling can be caused by dirty air filter.dirty throttle valve and bore.vacuum leak at egr valve and pvc valve.also idling too low.will cause rough idling.

Both the 1.6 and 1.8L 4cyl. engines have the pcv valve located in the valve cover @ top of engine. It's usually just pushed in a rubber grommet on the valve cover. Twist while pulling, and it should come out. Let me know how you make out.

Clean up the fuel sytem by spraying cleaner in the entire system with the engine on running at 1200 rpms. Clean the IAC (Idle air control valve) inside the fuel system. You will see 2 holes on the side of the hole inside the fuel cylinder after removing the air duct work. if not, the Idle position sensor may be bad.