96 Toyota corolla Idle issue


#1

Hello, I own a 1996 Toyota Corolla Manuel Transmission. Im currently experiencing an i idling issue. When i first start the car everything is pretty much ok. Until it finally heats up and reaches normal temperature. After that it boggs really low almost wanting to stall out. When im driving i have no issues it drives smoothly and shifts fine. This is a list of everything i have done so far:
Vacuum line cleaning
Throttle body and EGR valve cleaning as well as checked for cracks( after i cleaned this it seemed to help alittle)
Tune up (wires, plugs, cap, rotor,)
Changed the fuel filter
Ran lucas fuel injector cleaner
Cleaned the IAC

Not really sure what else to do. Thanks For reading and pleas help if you can.


#2

If you cleaned the IAC valve and still have an idle issue replace the IAC valve.

Tester


#3

Ok. Just one small question because im curious, why didnt cleaning it do the trick?


#4

Because the IAC valve is a stepper motor. So the motor doesn’t rotate but instead moves in a linear motion.

When the windings in the IAC valve short out the IAC valve doesn’t go to the proper position for the idle condition. So the engine doesn’t idle properly.

Any electrical motor in a vehicle wears out over time. Starters, blower motors, window motors, IAC valves.

Tester


#5

Ok thank you so much