'93 accord ex.is fine while driving, but runs hot when idling

My thought is to check and clean anything that has to do with idle air system. How long since a tune-up? Any applicable trouble codes?

did your mechanic change thermostat?

A weak or bad battery will power lights but not have enough current to spin the starter.

If it's running rough, chances are that it's misfiring. If the Check Engine light is flashing/blinking, it is definitely misfiring.
If that's the case, drive it as little as possible... Or straight to the mechanic because the more you drive it while it's misfiring, the higher the chance is of you ruining your catalytic converter.

I’m happy to help further over the phone at https://www.6ya.com/expert/jason_00b31cc8f593773a

If you get rough idling or the tachometer needle does not stay in one place when idling then you may have a dirty or faulty idle air control valve. This is a common cause of the problem you are describing. Other issues could be dirty MAF sensor or loose wires or vacuum hose.

the car is not recognising the key and is actuating the ignition cutoff (it starts then stops running straight away)try the spare key,if thats okay then you need to get the car/keys recoded as sometimes they do lose the ability to be recognised.

Have the Idle Control Solenoid Valve cleaned up.

Or it might be defective. See steps below to check...

1. Disconnect idle control solenoid valve electrical connector.
2. Disconnect upper hose to solenoid valve from manifold and apply vacuum to hose. Valve should hold vacuum.
3. Continue applying vacuum to hose and briefly energize valve by connecting battery positive terminal to the black/yellow wire terminal and negative battery terminal to the green/black wire terminal. Valve should not hold vacuum when energized.
4. If idle control solenoid valve fails to perform as outlined, valve is defective.

My 94 Sedan DeVille had the same problem. The car ran great but would stall whenever I stopped at a stop sign or traffic light. Turned out to the the TPS (Throttle Position Sensor). It monitors and controls the idle. What happens is the secondary idle (idle when the car is warm) is too low. Since all the controls for fuel mixture, idle etc are done electronically, they can't be manually adjusted. The TPS is the most likely cause of your issue. A diagnostic test (performed free at most chain auto parts stores) will be able to confirm this or lead you to another component. Best of luck to you!
Greg

You may have a problem with idle speed control motor or ETC as GM calles it. here is a photo and a price from rockauto.com.
STANDARD MOTOR PRODUCTS Part # SA4
Motor Assembly $110.99

what you have is a secondary ignition break down.replace spark plug wires and may cap and rotor.the should fix your problems.