Adjust your idle.
Put the engine into high RPM in neutral or park.
o2 sensor
The rpm's are not at a high enough rate when the car is idleing to engage the clutch plate on the compressor. To get the car to blow cold in park simply give it some gas to raise the rpm's. Belinda from Texas
It is normal for the RPM to increase a little when put in park or neutral. If the RPM increases by a lot, then you need to adjust your idle speed.
If it's a stick, it sounds like the clutch or clutch componets.
rev limiter will only let the RPM's get so high then it cuts back
Mercedes Benz SLK 230's engine will start cutting out at rpm's above 4k if the car is in park. This is a self preservation safety feature.
you may not be at a high enough rpm
Many things can cause lag while driving at a low RPM but not at a high RPM even if it is not the vacuum hose disconnected from the EGR valve as it could be the fuel filter. It can also be the park plugs.
It has a rev limiter. It designed to keep the engine from over revving and doing damage.
open or missing thermostat
Because bike engines Rev at high speeds typically 10k rpm as compared to 3 or 4 k rpm for a car