2007 impala car dies at stop light monitor flashed that engine throttle disengaged. car would not start right away but did restart. engine light stayed on

it appears you have electronic throttle control. any applicable trouble codes, relating to that system? clean the throttle bore and around throttle plate, don't force the throttle plate. your idle air is electronically controlled.

Tps is a possibility

Check the throttle body position sensor make sure its plunged in switch my be faulty.Unplug and see if car will start if so replace sensor .

You need to get the fault codes read to get the different faults and search what the codes mean to get a suggestion of where to look as sometimes the fault is upstream of the failed component

Or a Vacuume leak do you have a check engine light? Typically your TPS "throttle sensor" will throw a code when it is faulty

I’m happy to assist further over the phone at https://www.6ya.com/expert/brock_d67526d2a834c47e

If you have an engine light on you might ask autozone to read the code and tell you what's wrong. It could be that your spark plugs are worn out. If the spark plug gap is too great then that could cause stalls due to lack of ignition.

If the engine is flooding a big bootful of throttle all that extra air is likely to keep it running.

It could be something is causing the spark to disappear or it is fuel starvation. You didn't describe the systems - if injection perhaps the fuel pump stops when the starter is disengaged, similarly if the ignition is a ballast type the spark could stop...

I suggest a back to basics approach and monitor these things while starting/running.

Engine stalls or RPM fluctuates at idle.

This problem is commonly caused by a dirty automatic idle speed control valve and throttle valve but always run a OBD2 fault code as well as the cleaning procedure. Buy a can of throttle valve cleaner (do not use carburetor spray cleaner!) from NAPA or Carquest (made by CRC chemicals) and spray it into the air intake while the engine is running, use up about 1/2 the can, engine will try to stall hold the speed up, shut it down and let it soak for 30 minutes, restart and blow out the remaining fluid, shut it down and disconnect the negative battery cable for 5 Min's to reset the base idle control

It sounds like these things are all related. When the a computer sees a problem in the Electronic throttle system, it will dissable traction control, and give the reduced engine power alert because the powertrain computer does not know the value of throttle postion.
Codes will need to be scanned in the computersto begin diagnosis.
TechJK

1999 300M 150,000 Miles

Car dies when coming off acceleration or at idle in traffic or at a stop. I can watch the Tach go to 0 RPM, some times it will restart immediately other times it is hard to start, so far I have always been able to re-start it and Drive on. Does anybody have verified fix for this issue, I have seen posts saying can and crank sensor, throttle body, EGR, and many more ideas... Do not really want to just start replacing parts with the hope that I eventually get a fix. Help...