Trouble getting car to idle - 1998 Chrysler Concorde

Does this high idle speed happen when the vehicle is up to working temperature? Is the idle still even and smooth? It will idle higher when cold but it should drop once the engine is idling smoothly and is starting to warm up to working temperature. When was the last time the vehicle was serviced? Sometimes an old, clogged fuel filter can cause fuel supply issues.
The first thing I would suggest is get it plugged into a diagnostic system or an OBD2 scanner to look for Trouble Codes. This will cost you money so ask at 3 or 4 different garages for prices as the costs can be VERY different.
This could be a fuel supply control issue, an injector control issue or an engine management problem.
If you get the trouble codes comment below with them and I'll try to explain them for you.

Hello Carmelo Cortez,

The wise thing to do would be to get your codes read...
Beg, borrow or buy the FACTORY WORKSHOP
REPAIR MANUALS.... and trouble shoot yourself...

Alternative:
FREE technical service bulletins (TSBs) ...
and trouble shooting tips available for most popular USA market vehicle... (registration required) BBB Industries - FREE.
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My best advice would be to get your codes read...

Some parts houses & muffler shops will do this for free...
Even with the codes some of these issues can be a bit
of a riddle...

Not expensive nor difficult to do...

With your trouble seeming to be a cold issue...
Logically (Occam's razor) that would pint to your
(cold start) Idle air control valve ... Click here
1993 FORD EXPLORER 4 0L V6 Idle Air Control IAC Valve RockAuto

details
More Information for STANDARD MOTOR PRODUCTS AC23

More Information for MOTORCRAFT CX1828

Hope this helps

Carnac the Magnificent

troubles at lights may very well mean a vacuum leak from a faulty brake booster
test by stopping and then applying the park brake and taking your foot of the brake pedal
you can do this test in the garage
start the engine , apply the park brake , place in drive
if it idles alright , put you foot on the brake
if it plays up , replace the brake booster

Just curious why you think the idle is too low on your Grand Am. Do you have a SES/CEL onin the Instrument Panel? If so, take it to an O'Reilly, Autozone, Advance Auto, or your local Auto Parts store. Have them plug in the DIagnostic Trouble Code Reader to get the error codes. The DTC reader will probably give you suggested trouble/repair resolutions. Otherwise take it to a reputable auto repair shop.

Should not be anything above idle speed. You might get trouble Codes if too rich or lean at idle and truck may not idle well.

Impossible to diagnose without the trouble codes. Get the codes read and post here. ALWAYS start by reading the trouble codes to get a starting point.

I have a 96 Towncar, which had a P0125 trouble code set. I changed the thermostat and cleared the code - only to have it reset in a couple minutes after starting. The car was hard starting, and died several times before it actually ran. I did also noticed that while running the idle speed had risen to over 950 RPM.

I changed the Temperature sending unit located next to the thermostat housing, and again cleared the code. After starting the car again it performed excellently and did not reset the P0125 trouble code.

A few items not set correctly.
Idle rpm
Mixture and timing..
See no connection with transmission.
Mazda 626 from 2000 needing transmission work?
Normally Mazda's need virtually nothing.
Run 200.000 miles.
And they like original replacement parts.

Code 46 is indeed the trouble code for the Idle Speed Controller which is that big black box thingy on your throttle body. A lot of Chilton-type manual books omit that code because the ISC isn't found on pre 94 Metros. The ISC is a computer controlled auto-adjuster for the engine idle.

An important note: code 46 is often caused by misadjusted distributor timing. As you probably know, timing affects the idle, and if improper timing moves the idle beyond the ISC's adjustment range, the check engine light will come on and diagnostics will return code 46.

replace ignition coil make sure by dealer the right mode is used when ordering if not ordered right you will get a difference in engine volts