Engine surging up and down, hard to start, shutsdown when I remove my foot from the accelerator, sometimes stays at high 2000 rpm's while driving without using the accelerator

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?

Need to take to a shop with a GM tech 2 or higher scan tool. These tools can actually display various sensor readings and voltages in real time and can be used while driving the car to recreate the issue. These are super expensive scan tools so most shops don't have them. Call around or bite the bullet and have a dealer do it. The money you spend on a correct diagnosis will be saved by not throwing random parts at it based on guess work.

Check your idle air control valve

It sounds like a faulty idle air control valve. The computer uses the valve to control idle speed by regulating the amount of air entering the throttle body. Its possible the motor inside the valve is weak, or the valve is gummed up. I would unplug the valve when base idle is near normal and drive it for a day or two. If the valve is the problem the idle speed should stay in one place. And it should set a trouble code for the valve being disconnected.

Hi Richard, I'm not an expert on Jags, just a little jealous I don't have one. Looks like a very nice vehicle. Have a close look, inspecting all hoses and vacuum pipes on the intake manifold side of the engine for any damage or loose fitting. The problem seems to be a leakage of air which is raising the idle speed. Regards John

I have had the same thing and i got told that it was my idol control motor but after i got that it still does same thing if u find out what is wrong with it could u plz tell me

Sounds like you should not be driving the vehicle at all until the issue is rectified.

I hope I'm wrong but I think your torque converter is failing. Sorry, Gary

sounds like either fuel pump weak or fuel filter plugged

Here is the most common cause of surges and stalls, it is the idle speed control air-bypass valve and throttle valve, they get full of gunk over the miles and cause idle issues (stalls) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.