Rpm on 2001 grand vitars will dramatically drop at stop light

This code is set when the transmission control module detects improper voltage at the torque converter clutch. This can be caused by low tranny fluid/dirty tranny fluid/defective torque converter clutch solenoid/electrical connections to from solenoid

The first part is magic, (EFI system and good engine)
but?????
gauges go off can be a bad fuse or loose fuse to cluster.
when any Gas engine stalls. the RPM drops to 0
the EFI sees that and goes to key on, not started self test.
this is covered in the operator guide.
key light comes on KEY LIGHT, HUMMMMMMM
Let me look at the waring lamps, there are many.
one light is engine overheat that is logo of a thermometer but looks
just like a key.
http://dashboardsymbols.com/the-symbols/
is this a engine stall post
or engine runs perfect all the time , but only my dash acts funny
you didnt say?

key lamp?
immoblilzer (big trouble there)

a stall is anytime engine RPM drops to zero. called a STALL.
if your cars engine stalls, post that way, the lamps are all normal
on at any stall, on any car.
at a stall , rpm goes to zero and MPH drops to zero as you coast to a stop , stalled. that is all normal for any stall.

if engine stalls.
that is complex.
here is list.

1. lost 12vdc power to EFI system. (battery died, fuse blown)
2. never gave your car the 60,000 mile tune up, see opr, guide.
3. bad fuel.
4. overheated the engine.
5. engine oil gone, never ever checked at each fill up.
6. other more complex EFI system parts failures, ASK.

Most low idle speed problems on these engines are due to a faulty idle air control valve but since you state the idle will go up and return to idle then i would say it is working properly i think you have a throttle body coking problem ( dirt and grit accumulates around the butterfly valve in the throttlebody ) to fix this simply remove the fresh air hose from the throttlebody and open the throttle all the way up use a clen rag and wipe clean you may use a solvent such as B12 on the rag but dont use too much

first check for vacuum leaks, then check idle air control valve.
Please see my tip at http://www.fixya.com/cars/r7427423-fix_poor_idle_high_idle_stalling_fuel . These are generic instructions. If you getstuck or need specific instructions for your car, please get back to me with model, year and engine info.

I had the same problem and the cause was Vacuum problem and a map sensor. check those bad boys. Good luck

Do you have the idle speed turned up to keep it from dying? Because it is high. Check engine light on? Have you checked for vacuum leaks at the gasket under the throttle body? How does the car run under acceleration? You might have a worn distributor shaft.

Hello... Where to go next depends on how the Evap Gross Leak was fixed... Post it...

Thx.

Does that mean it does not stall or **** in 3rd gear?
The difference between low RPM and high RPM is primarily a greater fuel requirement. So a fuel related problem like clogged filter or bad fuel pump or return pressure regulator comes to mind.
Spark is also slightly RPM related, so you could have the ignition control module checked at Autozone or a place like that.
Other RPM related items, such as EGR, PVC, and tank purge valve are not likely to be so dramatic alone.

Try replacing PCV valve on the valve cover-had same problem one time on a 3100 I had.

Faulty injecters might be the problem. Pull a couple off and have someone turn the key to the on position and see if they are spraying properly