IDLE WILL JUMP FROM 800 RPM TO 1500 OR 2000 RPM. WHEN DRIVING, IT MAINTANS SPEED, WHEN MY FOOT IS OFF THE GAS PEDAL, AND WILL GAIN SPEED. THIS PROBLEM DOES NOT ALLWAYS HAPPEN, BUT IT SEEMS TO BE GETTING MORE OFFTEN

FORGOT TO SCAN THE PCM I SEE.
check all fuses.?
not told
fails hot and cold engine or both
car must be in transmission DRIVE selected? right?
and foot off gas pedal (accelerator)_ rpm goes to 2000 or up to 6000 rpm . and or
so driving foot off the pedal and RPM goes too high
or in drive, I step on the throttle (gas) and RPM shoots way high
and Never leaves 1st gear. that is transmission failures.
in DRIVE.
if rpm also goes that high right foot doing nothing and in park
that is engine idle control's failing.
we can not see you drive or how. so answers can be a tad hard.
in what gear? PRNDL (choices)
right foot doing what?
and what SPEED is too slow 20 or 85mph? or?
does tranny fail to upshift?

There is idle in park and idle in drive not moving. The difference should be about 300 RPM. Are there any code being shown on the TCM or ECM

replace the idle control sensor to get an idle speed above 800
run the fault codes as there may be more wrong that need fixing

You have a mechanical bind. Disconnect the main linkage and work it all by hand. Everything should be free and slopy. Aerosol carb cleaner will help, but only when the engine is not running.

almost sounds like the cruise control is engaging

its because or engine rpm is below 800 when u remove your foot from the gas pedal, try adjusting your engine rpm to 800 or above to get a smoother idle speed

I'd hazard a guess that the torque converter disengages from "lock up" when you lift your foot. This would let the engine instantly idle down, and would produce no braking effect from a closed throttle.

Try driving it (at a lower speed) in direct, rather than overdrive, and see if the same thing occurs, or if you get the expected braking effect when you lift your foot off the throttle.

Have the idle bypass valve checked, also called idle air control valve.
If that valve is stuck in the closed position, it's not allowing the fuel to bypass the throttle plate to keep it idling, resulting in stalling, but will keep engine running if the pedal is pushed down.

There is a vacuum leak somewhere in the intake system. A very common problem on these cars is a PCV valve that gets stuck open and replacing that first is very cheap. If that doesn't solve the problem, then you'll have to go hunting. Listening very carefully for a hissing sound in the engine compartment will often lead you to a hose that is off or a gasket that has failed. You can also spray small amounts of aerosol carb cleaner at suspect areas to confirm the leak. The engine will change revs when fed the carb cleaner.

The idle air valve (located below the throttle body) provides the control for constant idle speed. In order to set the correct air valve opening to achieve constant idle speed, the fuel injection control unit uses information from the air mass meter, throttle valve switch and the ignition control unit (RPM signal) to regulate the output current to the idle air valve. This means that the idle valve is not affected by air leaks or a jammed throttle valve.