Hi I had this problem. make sure your water level in the radiator is full,because there is a sensor kelvin
Is the AC turned on?
There can be many reasons why a car surges while idling. Some of these reasons are the computer could be dying, or the fuel injector are giving the engine too much gas.
Not without electrical work. The 1997+ Preludes have OBD2 wire harness while the 92-96 Have OBD1. Different wire harness/sensors/ecu.
main relay
Valve adjustment needed is a possibility.
vacuum leak
IAC (Idel Air Control Valve)
It is safer and improve handling while driving in higher speed.
The front seats can be swapped out. The rear seats however cannot, as the 92 model had a partition down the middle, while later models in that generation had a more standard seat setup.
Loose nut behind the wheel. Loose nut behind the wheel.
If its computer controlled engine, it more than likely a dirty or bad Idle Air Control Valve.
I think I'd check for a loose, cracked or missing vacuum hose somewhere under the hood. FriPilot