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I just test drove a SE, which ill probably end up with...

but the air con under the glove box has a hiss to it.

i didnt have a good chance to check it out under the dash, but it didnt seem major and it all looked good.

the air con is still icy cold and everything works apart from the hiss.

the owner did mention that a pipe was replaced under there a while ago........ as there was a minor leak of water there.

oh, and the hiss does not stop immediately when the car/air con is shut down it was a gradual decrese in the hiss.... not immediate, which leads me to believe that its not fan related, but condenser related.

Thoughts?

All the MX-5s I have dríven hiss.

My previous NA air con hissed but no cooling issue whatsoever. However my current SE doesn't hiss.

Mine hisses.

well it sounds like the hiss might just be the running compressor.

It's just the compressed gas expanding into the evaporator...all aircons hiss (if they didn't they wouldn't be working) it's just that some have more sound insulation to hide it.

thanks

i didnt think it was a major problem (as the owner said its done it the whole time, and the A/C still pumps icy cold air)

just wanted to be sure before i potentailly buy a problem.

Guys FYI

spoke with my mechanic mate

said it COULD be a TX valve.

Imagine it being like a wastegate for your A/C its a spring loaded valve that regulates the gas pressure.

Also could be over/undergassed........


will be checking the problem out in due course.

The AC hiss is usually a low charge of gas, when fully charged hiss should be minimal.