She's a moaner

[gray]

This is for the guys out there that never hear her moan;
my girl moans, but only when the temp is right.

OK, lets get back on track;
the problem is this; my 1996 FZJ-80 moans, yes moans if the
conditions are right.

When the ambient temp is say above 70, and only when under slight acceleration, a light pedal, she will moan and it is a moan, kinda like a Whaaaaa. It seems to be coming from the dash to the left
of the steering wheel.

I can keep her doing the moan as long as I keep my foot in
the exact same place with the exact same constant pressure;
if I push harder, or let up, she will stop moaning, immediately,
and no second chances to try again; she is stubborn that way.

On the other hand when the ambient temp is colder, say around 40 or below, she will moan, but in this scenario, she will moan when decelerating, say when coasting down a slight grade with the foot off the accelerator pedal; she does not do this very often, but has a few times.

So, for all you techies, what is causing this moaning?? I have some
ideas, but thought I would let you guys drool over it a bit.

Serious replies only; all others will be handed over to my massage therapist.

g

 

[landtank]

that would be from a dry shaft. You need to get some lubrication down there. It's a tight fit and the lack of lubrication especially when cold causes an increase friction.

Search on spindle bushing.

 

[gray]

that would be from a dry shaft. You need to get some lubrication down there. It's a tight fit and the lack of lubrication especially when cold causes an increase friction.

Search on spindle bushing.

OK, it is hard to tell if you are serious, or not

Maybe I did not describe the sound well enough;
it is not a squeak, or grinding, or whirring, or whining, (or yelping with glee), it is a moan; whaaaaaaaaaaa, which continues to increase in volume (crescendo) as I keep my foot in the same place (on the accelerator pedal that is). It stops immediately if I lift my foot or give her more gas.

g

 

[gray]

Imagine the sound that a trumpet would make when it has that plug thingy in it ie: from a 1930's
musical with Fred Astaire; it is a rising note musical-like sound coming from the dash. It seems to be inside the car; not heard outside, and not a mechanical something-is-binding/grinding sound.

g

 

[Darwood]

Most likely Landtank has it right. I've never heard a dry spindle bushing so I don't know. Oh and yeah he was being serious.

 

[landtank]

yes Gray I was being serious. I fought a dry spindle bushing for a few months. In my case it would come in an instant and only last for about 5 seconds. I finally got a sound bite of it and with help from others on this forum I tore into my front axle and took care of it.

 

[gray]

yes Gray I was being serious. I fought a dry spindle bushing for a few months. In my case it would come in an instant and only last for about 5 seconds. I finally got a sound bite of it and with help from others on this forum I tore into my front axle and took care of it.

The sound seems to be linked with changes in engine vacuum;
ie: during slight but constant acceleration on a level or near level road, and it is coming from behind the dash, to the left of the steering column.
Once when I took it to a dealer, they sprayed a ton of silicone spray into the left air duct thinking it was from a stuck door.(not very smart
guys) But the point was, they heard it, and thought it was
due to something wrong with the HVAC system. Even had the door motor replaced on the HVAC system.

My thoughts are the brake booster, as it is in a straight line from
where the sound is coming from.

Anyone out there every hear of a brake booster making noises??

G

 

[gray]

Forgot to mention; had my hubs serviced; no change in this noise before or after.
g

 

[concretejungle]

my guess is that you have a very tight tolerance on the exhaust somewhere, and when your motor has a certain load on it, it's causing the motor to torque or twist just enough to get the exhaust to touch on the chassis or slider or frame rail just enough to sound like a moan.

I'm guessing this because it happened to me. My exhaust would touch on my slider rail at just a certain pedal position.

 

[gray]

my guess is that you have a very tight tolerance on the exhaust somewhere, and when your motor has a certain load on it, it's causing the motor to torque or twist just enough to get the exhaust to touch on the chassis or slider or frame rail just enough to sound like a moan.

I'm guessing this because it happened to me. My exhaust would touch on my slider rail at just a certain pedal position.

Nope, it sounds like a musical instrument; whaaaaaaa;
not a rumble, not a grinding, not a revolving or rotating-type noise,
not a whirring, not a first, second, third (etc) order vibration transmitted through the chassis; it's a musical sound, really.

If you had your eyes closed and heard it, you would think that a kid(or midget hidden in the dash) had a little toy horn or trumpet in the car, but on the other hand, it is not like an electrical or digital sound.

And it is very noticable, not any faint off in the distance thing.
It is like no other sound I have heard in a vehicle before.(?X Files ).

Maybe if I can somehow record it; but it is infrequent; no way to
predict when it will happen.

It is a head scratcher for sure.

g

 

[landtank]

my wifes 96 4Runner had a similar noise coming from the charcoal canister. There was even a TSB on it. It had to do with pressure changes and a check valve, all part of the canister itself.

 

[gray]

Anyone know if brake boosters can make noises? This noise is not a hissing, or ticking, or buzzing,
or clicking, or whining; it is like a wind instrument inside the dash. The closest note I can compare it to is like a low pitched ?Kazzu, that kid's or New Year's Eve toy noise maker, but lower pitched than one of those, not so tinny a sound; whaaaaaaaaaa with a continuous increase in volume as I slowly accelerate. It stops immediately if I change the position of the accelerator; ie: just the slightest move
or my foot ie: change in the pedal pressure, and it stops.

g

 

[Romer]

Have you looked at your muffler to see if any of the connecting piping is cracked?

 

[gray]

Have you looked at your muffler to see if any of the connecting piping is cracked?

This musical wind instrument-type sound is inside the vehicle;
not the engine compartment, not underneath, not coming from the outside, but inside the cabin; coming from the left side (DS) of the dash; really.

It is not a high pressure exhaust type sound (I have that one
on take off, coming out of the tail pipe), not a sound like
escaping air or exhaust, not like an exhaust leak;not like
any of the dozens of different engine or drivetrain type sounds we all have heard; it is a musical sound; WHAAAAAAAAA; (make that sound
yourself out loud) that is what it sounds like, but more
like it is from a cheap musical wind instrument.

g

 

[scottm]

Mine does that occasionally. I thought it was common for the power steering pump to moan. Maybe all those threads were about some other moaning sound? I changed some fluid a few months ago, it doesn't seem to do it as often, but still occasionally moans in the morning. It's a fairly "pure" note, not a complex sound, doesn't vary directly with speed.

 

[gray]

Mine does that occasionally. I thought it was common for the power steering pump to moan. Maybe all those threads were about some other moaning sound? I changed some fluid a few months ago, it doesn't seem to do it as often, but still occasionally moans in the morning. It's a fairly "pure" note, not a complex sound, doesn't vary directly with speed.

Nope, not a pump whine,
it is coming from the dash, or at least is transmitted through the dash.

My best guess, as it seems related to vacuum, is that it is coming
from the brake booster and then being transmitted through
the firewall as it seems to be coming from the dash, almost
out of the left air duct. I thought a long time ago that it was due
something wrong with the HVAC system; like a stuck door,
causing air to get sucked through a narrowed opening;
even had the vent door motor replaced when under warranty, no change.

g

 

[concretejungle]

well, my second guess would be muffler bearings.

 

[landtank]

this thread is heading in the same direction as some of my technical help sessions.

tech: "I have this problem"

me: "it might be this"

tech: "nope"

me: "or this"

tech: "nope"

and so on until everything has been mentioned at which point I reply: "you don't have a problem"

 

[Cruiserdrew]

Gray-If you are at all thinking the booster might be involved, then do the test described in the FSM. In 30 seconds, you'll know if your booster is airtight, and if it is boosting brake pressure appropriately.

My money is on the power steering pump, because it doesn't always whine, like when it's low on fluid. I have heard them make a noise you could describe as a moan. In fact, some ih8mudders, add Downey fabric softener to prevent it. Note, I am not recommending that, but even Cruiserdan has agreed with the practice.

Could it also be the mechanism that moves the air vent baffles?

 

[gray]

Gray-If you are at all thinking the booster might be involved, then do the test described in the FSM. In 30 seconds, you'll know if your booster is airtight, and if it is boosting brake pressure appropriately.

My money is on the power steering pump, because it doesn't always whine, like when it's low on fluid. I have heard them make a noise you could describe as a moan. In fact, some ih8mudders, add Downey fabric softener to prevent it. Note, I am not recommending that, but even Cruiserdan has agreed with the practice.

Could it also be the mechanism that moves the air vent baffles?

I think the key point in all my descriptions is that it is coming from
the dash; it is absolutely positively not coming from the engine or
an engine component. The brakes work fine, plenty of pedal,
correct pedal feel, no loss of pedal pressure, etc,etc.

Maybe the description of it being a "moan" threw some off track;
it is a whaaaaaaaa, coninuous and rising as long as I keep
the pedal in exactly the same position; the instant I move
the pedal, it stops, if I then hit the pedal again, no noise.

The only reason I thought it may be the booster was because it has a sound like you would imagine a vacuum might make (booster works on vacuum) and because the sound is coming from the dash right behind the booster.

It only does it rarely and only while under light acceleration,
and if the pedal pressure is changed even slightly, it goes away,
and may not reappear for 3 weeks, or, it may come back in 3 days.
But never sequentially and I can not make it happen on demand.
It does it when it wants to.

One dealer thought that it came from the air handling baffles or doors and sprayed a ton of silicone lubricant straight into the left air vent on the dash. All that did was make for a sticky vent.

Is it a problem?? probably not as this vehicle has done it for about 6 years; no worse, no better. It is more of a curiosity, that is why
I brought it up. Thought that someone may have experienced
the same thing and knew what it was.

I'm am sorry to those who find this frustrating; I have found this frustrating as I have mentioned it to half a dozen Toyota mechanics
and they either think I am wacko, or just walk away scratching their heads.

G