3-Series (E46, E90)Chat relating to the BMW 3-Series from 1999 to Current. Models include: BMW 316i, BMW 318i, BMW 318Ci, BMW 320i, BMW 323i, BMW 325i, BMW 330i, BMW 328 Ci, BMW 328i, BMW 325i/xi, BMW 330Ci, BMW 320d, BMW 330d, BMW 335d.
Just found this site and hope I can get some answers! When the A/C in running it makes a hissing or high pitched noise, though it is not very loud. Is this just the compressor cycling? Anyone else have this noise/ Thanks.
Depends where you hear the noise, a hissing noise heard from inside the car is more likely it's low on refrigerant gas. When the gas passes the TX valve, it tends to make this noise when gas is low.
I don't think it would be the clutch fan as it's not entirely for A/C.
Outside the car in the engine bay is another story. If this is the case, get it check out, shouldn't be too hard to find, there isn't much to a/c system.
:-) when gas is low, the compressor will be disabled- there is a safety pressure switch on the low side of every automotive A/C system, tht serves as a breaker when the system is low on gas or absent of freon.
i said magnetic clutch & not fan clutch :-).... the magnetic clutch on A/C compressors is the black pulley head where ur belt connects to ur A/C compressor. Note it's operation when ur A/c is on/off and you'll see what i mean ;-)
um, I did thought u were talking about fan clutch, lol, my bad.
However, a/c will not turn off unless it reach a very low level, it will still work say with 1/2 or even 1/3 of the pressure in the system, and that's when it will make that noise.
If you live in melbourne, you come to my work, I'll show you.
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