I have a 1994 honda prelude vtec. the cars temperature rises above usual when car is idling and stationary. The cooling fan comes on but late.

Transmission could be running hot. Most times tranny fluid also runs through the sides of the radiator. Or a transmission cooler somewhere near the radiator and in some cases will make temp gauge rise

Run a cooling system pressure test. If you are losing pressure, then you will have to first locate the source of your leak.

With the engine started and the radiator topped off with coolant, does the radiator spout water out of the top? Does the spouting become more aggressive with engine revs? Yes? = Blown head gasket, or cracked cylinder.
No?- check operation of radiator cooling fan. With car stationary and hood up, run engine up to temperature and make sure radiator cooling fan kicks in before the engine temperature rises too high.

when stationary their is no air flow through the radiator so temperature will rise and the cooling fan comes on ,now as for it not going off then this could be a sensor ,relay or the computer as the sensor tells the temperature to the computer which turns the fan on and off ,now on these cars the fan will stay on for up to 5 mins after turning the engine off so if after this time it hasnt gone off then consult the dealer as you have bought a asian market software vehicle so it will not respond to a code reader to locate any faults just like the europeon version but the american version can be read with a code reader .

1. Make sure your coolant is at the proper level in the overflow tanks as well as in the radiator.
2. Make sure the cooling fan is working properly (note as a quick check, turn on the A/C. It should come on with the A/C on regardless of engine temp). When the car is stationary your radiator relies on the electric fan to move air through it. When you are moving air passes through without the need of a fan.

Usually the fan only comes on when you idle, when you are cruizing along the fan doesn't need to be on unless the car is running hotter than normal. It is controlled by a temp switch. I would check your coolant, let the engine idle and see if it comes on. Then if it doesn't, look for a fuse, bad wire, bad fan motor, etc.

The cooling fan is required to operate when the engine temperature rises above the maximum operating temperature threshold.
After the car is started, it will usually take some time for this temperature to be reached.
Ensure fan runs when fan control temperature sensor switch demands.

Possible speed sensor. I know the speed sensors are a problem with hondas. A new speed sensor is about $200 and can be easily replaced. It bolts to the top of the transmission on the firewall side. Do NOT buy an e-bay one. They are only about $30 but are junk

Try replacing Oxygen sensor (top of exhaust pipe just rear of engine; 22mm ring-spanner job after cutting wires); though normally comes up with Code 1 on the MIL, this is the right bunch of symptoms.

The thermostat is starting to stick .
Replace the thermostat.

Intake valve clearance 0.15mm-0.19mm (6-7 thou); Exhaust clearance 0.17mm-0.21mm (7-8 thou). All measurments COLD engine. 2.2 VTEC Prelude engine 1992-1996, import and UK.