jonas's RX

Hi everyone

I have owned 2 SC and I notice both of the SC I have owned get a odd " hissing " sound
when the ignition is turned to the " On" position with the key located in the engine area
It will come on and then go off

Sometimes this " hissing " sound will come back on when driving and then off again

Have anyone heard this " hissing " sound when the key is turned only to the
" on " position ?

Thanks for your feedback

mrblister

Define Hissing Is it like from a sound from a speaker or is it a gurgling noise behind the dash.

jonas's RX

I can hear the noise coming from the engine compartment . It is like a fuel pump, ABS or a relay coming in and then off It is more a light low humming sound

When you turn the key to " on" and not start or cranking the car , does anyone hear any low humming coming from the engine compartment ? It is clear there is a low noise . I have one SC I sold and now another one and they both emit this same noise

Tx

mrblister

Actually you can get noise from the fuel pump also amplifier fan running I believe that your abs can produce sound also actuator for air cond heating. Others may add to this thread I have not experienced this or maybe not paid attention

jonas's RX

The low humming noise is very obvious and it will come on when you turn the key
to the " on" position without cranking the car

Sometimes it will also come on and then off when you are driving the car

Does everyone hear this low humming noise ? It happens with both of my SC

I guess it is not a big concern but it is there

Coleroad

And then there is the fuel vapor leak detection pump . There are many relays motors pumps vacuum actuated components on cars.

mandyfig

I must say the above is closest to what I think it is. When you start your car, the 1st exhaust gases go to the charcoal canister, hence the need for the infamous EGR valves. You need heat to get your catalytic converter running to burn the bad gases.

jonas's RX

Are you guys all hearing this low emitting " humming " when you turn the key to the on position ?
It will also come on in occasions and then off when driving the car

I am pretty sure this was also the noise I heard in my 04 SC with 53K As well
Before I bought my current 03

It is not a buzzing or a whining of moaning noise but a low humming
noise

Otherwise the SC has been solid all around

Just changed timing belt , pump and all belts ��

Cheers

texsexlex

iTrader: (3)

...Jonas I've noticed this sound also, but hadn't put much thought into it. I originally thought it might be the fuel pump,but since that's behind us, I ruled that out. I also thought it could be something dealing with the automatic climate control/ ac..but again,since there wasn't any issues with the car,I just figured this was something that all Sc's did .....now I don't recall it happening off/on while driving the car.

jonas's RX

TX texsexlex

This low humming noise is noticeable when you first put the key In the " on " position

Sometimes you will hear it come on and then off when driving

I am just curious is this common for the SC

Cheers

Bgw70

How long does it last?

I turned my key on and heard the fuel pump, antenna, HVAC servomechanism adjust the air defectors inside the dash and the boot sequence in the engine compartment.

Everything was complete within 15 seconds, then silence.

If you are hearing more of a humming sound, it is most likely the fuel pump.

If you have a smart phone, use your camera and create a video, then post it to YouTube.

jonas's RX

Hi BgW70

I will try to post it on you tube but the low humming you mention
Is usually when you put the key in the " On " position

It will sometimes stay on and when you start the car and then off
does this sound like a servo ? It is definitely coming from the engine
Area . I opened the hood and it looks like it is coming from the firewall
And the engine .

What is a boot sequence ? What is an air deflector ?

Tx

jonas's RX

Here is the YouTube gang

Coleroad

I'm leaning towards it being the abs that is making the sound

texsexlex

iTrader: (3)

...I think mine is probably the HVAC, it only last 10-15 seconds