Wehn hot, AirCond kick in, RPM drops till base line.

[iceburnt]

Hi ZTHians,
i got some problem with my Integra GSR. When I start my car in the morning, the engine revs does fine 750RPM idle without aircond turned on. However when the weather gets fairly hot and i switched on the aircond, the engine's revs at very dangerous low level.
I have done research on the net and some forum did mention that main relay tends to fail when the enviroment gets hot. but the simptoms from main relay failure is fuel pump doesn't work and the engine doesn't start. Mine's is not that serius but without aircond in the hot weather.. :egg:
Please anybody can help me solve this problem.
TQ

 

[budin99]

I had experince on this situation.

Check your aircon fan whether it is working when u turn on aircond.
The term relay not function might was due to aircon motor's relay not function. If the motor does not work, your rpm will be very low like dragging all your engine power.

If the motor does work, then u might suspecting your throttlebody.

If not? let others sifus anwer for you. cheers.

 

[shiroitenshi]

or....

1) idle valve not working properly, due to blockage or possibly faulty unit.

2) vacuum/air leak

3) aircond compressor is feeling tight, due to belt overtension, or simply the compressor failing.

 

[iceburnt]

Tq sifu... but forgot to mention. The fan did working. Sometimes even when i didn't switch on the aircond, when the engine has warm and the fan spin to cool off the engine, the rpm meter also drop very low. I am suspecting the throttle body or idle valve. Especially when i'm stuck in traffic jam and the car not moving (in hot weather), the engine gets hot and there come the terrible moment. Sometimes, the funny thing is, when the fan is spinning to cool the engine, i can feel cold air going through my aircond hole eventough i didn't switch on the aircond.
haiya. buying this car give me headache.

TQ in advanced to all sifu

 

[soulfly]

most likely it's the idle valve.
fan is not supposed to spin when engine is cold. it will spin at normal operating temperature.