4.6L Lincoln TC noise when engine is OFF

I have a '99 Town Car, 4.6L. Periodically when the engine HAS BEEN OFF
for a while, there will be what sounds like a whirring or buzzing sound
that lasts 5-10 seconds. By chance I was able to approximate where it
was coming from one day when the hood was up... sound was coming from a
compartment between the air filter box and driver's side headlight.
What the heck is this and what does it mean?

> wrote in message
oups.com...
> I have a '99 Town Car, 4.6L. Periodically when the engine HAS BEEN OFF
> for a while, there will be what sounds like a whirring or buzzing sound
> that lasts 5-10 seconds. By chance I was able to approximate where it
> was coming from one day when the hood was up... sound was coming from a
> compartment between the air filter box and driver's side headlight.
> What the heck is this and what does it mean?
>
Level ride compressor. s

sdlomi2 wrote:

> > wrote in message
> oups.com...
>
>>I have a '99 Town Car, 4.6L. Periodically when the engine HAS BEEN OFF
>>for a while, there will be what sounds like a whirring or buzzing sound
>>that lasts 5-10 seconds. By chance I was able to approximate where it
>>was coming from one day when the hood was up... sound was coming from a
>>compartment between the air filter box and driver's side headlight.
>>What the heck is this and what does it mean?
>>
>
> Level ride compressor. s
>
>
Which should not run when the ignition is OFF.

"Mike Behnke" > wrote in message
...
> sdlomi2 wrote:
>
>> > wrote in message
>> oups.com...
>>
>>>I have a '99 Town Car, 4.6L. Periodically when the engine HAS BEEN OFF
>>>for a while, there will be what sounds like a whirring or buzzing sound
>>>that lasts 5-10 seconds. By chance I was able to approximate where it
>>>was coming from one day when the hood was up... sound was coming from a
>>>compartment between the air filter box and driver's side headlight.
>>>What the heck is this and what does it mean?
>>>
>>
>> Level ride compressor. s
>>
>>
> Which should not run when the ignition is OFF.

The suspension stays active for something like 30 minutes after the key is
turned off. It sounds like normal operation to me.
Bob

the Lincoln I have does the same thing.

wrote:
> I have a '99 Town Car, 4.6L. Periodically when the engine HAS BEEN
OFF
> for a while, there will be what sounds like a whirring or buzzing
sound
> that lasts 5-10 seconds. By chance I was able to approximate where
it
> was coming from one day when the hood was up... sound was coming from
a
> compartment between the air filter box and driver's side headlight.
> What the heck is this and what does it mean?

Chiming in late...

Yes, it is your rear suspension pump assembly doing its job. It is
located under the hood. They do operate with the key off - its
leveling the car after you get out of it. It takes about 10 seconds to
decide that the ride level has changed long enough to require
compensation. Be thankful that yours works, because they have a pretty
high failure rate.

Toyota MDT in MO

"Mike Behnke" > wrote in message
...
> sdlomi2 wrote:
>
> > > wrote in message
> > oups.com...
> >
> >>I have a '99 Town Car, 4.6L. Periodically when the engine HAS BEEN OFF
> >>for a while, there will be what sounds like a whirring or buzzing sound
> >>that lasts 5-10 seconds. By chance I was able to approximate where it
> >>was coming from one day when the hood was up... sound was coming from a
> >>compartment between the air filter box and driver's side headlight.
> >>What the heck is this and what does it mean?
> >>
> >
> > Level ride compressor. s
> >
> >
> Which should not run when the ignition is OFF.
I think that if you investigate further, you'll find that it DOES run
when ignition is off. We (3 of us) sell ~1500 cars a year, many of them
have level ride, and many of them do run with ign. off. What used to scare
me more so than those compressors--literally--was when I first experienced
cars whose electric fans, after the car had been switched off and locked up
for the nite, suddenly started running. Some things, I agree, just seem to
defy our common sense/everyday expectations. s