There are several possibilities. A good starting point is check for trouble codes by running a diagnostics check. I say this because there several ssensors needed for proper operation of your car and anyone of them could be bad or going bad. This is not for a beginner to do, because if you do something wrong you can really mess your car.
A Ford Escort might not idle properly if the throttle position sensor is not functioning properly. This part is a plug in that is on the side of the carburetor (throttle body).
where is the idle control motor for a 1998 ford escort
Fast idle motor is not functioning properly.
Idle speed control or Idle air control.
The idle setting for a 2001 ford escort zx2 is something that is not owner adjustable. It the idle is off, check for vacuum leaks or a clogged air filter.
The idle speed control valve was bad.
have lost my idle on a 1995 mitsubishi--what is the problem
The car was staying idle.
The idle air control valve on a 1990 Ford Escort is located on the intake manifold. An idle air control valves function is to control the amount of air that is allowed to enter the engine so the idle can stabilize.
There is more than likely a problem with the idle arm censor that would cause this. There may also be a problem with the throttle body.
go to autozone.com
750 rpm