Ford Repair: I have a 1993 Ford Crown Victoria...., ford crown victoria, dashboard lights

Question
I have a 1993 Ford Crown Victoria. It runs fine as long as the car is going down the road, but when I am stopped at red lights or idiling the motor starts sounding like it is having power surges and the car goes dead. It always starts right back up. If it is at night, all the dashboard lights dim every time the motor surges. What could be the problem?

Answer
Since your concerns are only when the car is at idle, I would first look at the idle air control (IAC) valve on the intake manifold.  You didn't mention whether the 'check engine light' comes on, but I suspect it does because the PCM monitors sensors and outputs, setting trouble codes when something is not within the expected range.  The electrical dimming is likely due to the engine RPM fluctuations, and will not be an issue after the idle is stabilized.
A scan tool would be helpful, to read the codes and then to monitor the IAC commands.  Without a scan tool, you could unplug the IAC and see if the idle will stablize with just a slight amount of throttle opening (a warm engine should barely idle with the IAC unplugged - something like 450 RPM).  If the idle is now smooth, albeit low, and the electrical system is now stable, you need an IAC.
You also might clean the throttle body with some 'sensor-safe' carburetor cleaner to remove the carbon deposits that have accumulated.
Hope this helps...
Happy New Year!
Clay