Unkle

Hi

Does anyone else have this?

Non AC car

When my heater is set to full hot, or full cold it doesn't make any noise, but if i set it to 21 to 26 temp it seems to make a small whistle that pitches up and down like it can't make up its mind how much heat it wants to allow in. I cleaned the small fan on the back of the heater unit but I'm not sure that had any affect.

Does a sensor or vent need cleaning of lubricating?

John Boggiano

Mine does it it I have both sliders closed. Just cracking one open a little bit stops it.

Unkle

thanks John, yeah i tried that, and every permutation, but the only way i could stop it was with the temp. I assume the temp fully opening something and fully closing something (Great technical explanation i know) must set flaps open or closed, but in between results in a air releasing whistle or hiss that pitches up and down...

PaulW_964

I have the same issue, will check the position of the the sliders next time I take it out... bloomin annoying though isn't it!

boxsey911

I have it too....seems to change in intensity with road speed too.....I just put it down to being one of those idiosyncrasies of the 964 HVAC system

Unkle

Yeah its annoying,

With the radio on its ok but i prefer not to put it on, at least i'm not the only one, and if its a feature that occurs i will leave it.

But if the sliders (not sure where or what they are) can be cleaned or... i am happy to tinker with it.

@ Paul are the "sliders" something under the plastic panel under the hood? Or do you mean sliders somewhere else.

PaulW_964

I assumed John was referring to the sliders on the dash.

Absolutely Steve, if we can't find a cure, we 'will' learn to love it

Unkle

I'm an idiot, i thought you were referring to some kind of technical venting system behind the bulk head that regulates the hot air.

PaulW_964

Ha ha not at all, he have been referring to something like that... perhaps I'm the idiot?!

nidon

Of no help at all but mines the same, can play tunes with the sliders

Unkle

I read Johns post, replied, and still thought you were talking about something else.

@Nidon If you have the same issue as me sliders don't seem to help only the temp dial helps, although it sounds like i have a couple of baby Clangers behind the dash somewhere..

But at least with it baking hot the car stays a little cooler

DaveK

It shouldn't be temp dependent - so it's probably not this - but are you sure it's not the front fans? Mine has been making noise on and off for several years from the front fan (sounds more like trapped crickets than clangers though). When I find the enthusiasm, I take the firewall out, take the cover off and spray some grease in there which usually shuts it up for a year. Obviously that's almost as much work as actually replacing the fan - but you don't want to know how much they cost..........

Unkle

The sound doesn't cycle like a fan sound unfortunately. It may take as much as 4-5 sec to get high pitched and the same time to get back down. The sliders open, closed, vents open or closed don't change the sound, but put it on full cold or full hot stops it...weird.

This will sound dumb - I thought this might be because something must electronically control the flaps that allow the air through to the cabin and may be they are fully closed or fully open when the heater dial is maxed out either way. Only when the medium temp is selected do they partially open allowing in the mixed medium temp air and for some reason they can't sit still and move open and closed, creating this sound.

DaveK

I think you mean "fortunately". Those front fans are something ridiculous like £500 each (one each side) plus labour to fit!

Unkle

Yeah sorry my mistake,