Squeak under engine deceleration

[nmos]

My 1997 OBS just started making a high pitched squeak.  It's mainly noticeable at low speed when I let off the gas (engine braking only).  It doesn't happen at all in neutral when I rev the engine or with the clutch all the way in and sounds like it's coming from the front.   The last work was a right front axle replacement about 4 months ago.  It doesn't sound like a belt or brakes (quieter but higher pitched).

 

Any ideas about what this could be?

 

--

Ray

 

[nipper]

Hrmmm this is hard without more clues.

 

can be a motor mount. COuld be a belt. How old is your timing belt.

 

Is it a squeek or a creak?

 

does it happen warm cold or all the time?

Does it happen straight or turning or all the time?

Why am i tempted to make this a Dr Zeuss rhyme?

What happens when the AC compressior is engaged?

[1 Lucky Texan]

was the intake air filter replaced? maybe it wasn't seated well where the tabs go in and high vacuum is making it whistle?

 

have you inspected the brakes? Maybe the inner pad is dragging its squealer. (inner pads almost always wear more than outers)

 

maybe a pebble between the rotor and brake shield.

[nmos]

Hrmmm this is hard without more clues.

 

can be a motor mount. COuld be a belt. How old is your timing belt.

I replaced the timing belt about 100K ago so it's probably time again but I've heard lots of worn belts over the years and this sounds different.  Also I can only hear it when it's in gear and moving.

Is it a squeek or a creak?

It sounds "metal on metal" to me, a bit like completely worn out brake pads but not as loud and, of course it's not happening when I apply the brakes.

does it happen warm cold or all the time?

Definitely when warm  but I'm not sure about cold.  My wife normally drives this car so I only heard it for the first time today after it was warm (she mentioned it maybe 2 days ago).  I'll see what it's like in the morning.

 

Does it happen straight or turning or all the time?

Definitely in a straight line but I haven't tried turning while it's happening.

Why am i tempted to make this a Dr Zeuss rhyme?

What happens when the AC compressior is engaged?

I'll give it a try in the morning and let you know. 

 

One thing I noticed is that it's easier to induce the sound in reverse.  While going forward I can also induce it by accelerating and then suddenly letting off the gas so there is significant engine braking  but once the car slows to the point where there is little engine braking then it stops until I down shift.  In reverse I can here it while accelerating but it goes away when I let off the gas.

 

One thing, and I hesitate to mention it because it could send this off onto a wild goose chase but one of my power steering lines is leaking.  I noticed it about a month ago but have been waiting for the weather to warm before dealing with it.  I've been keeping it topped off but maybe that fluid has gotten into somewhere it shouldn't?

[nmos]

was the intake air filter replaced? maybe it wasn't seated well where the tabs go in and high vacuum is making it whistle?

 

have you inspected the brakes? Maybe the inner pad is dragging its squealer. (inner pads almost always wear more than outers)

 

maybe a pebble between the rotor and brake shield.

 

I haven't replace the air filter in far too long and it really doesn't sound like that sort of whistle.  I'll try pulling the front wheels tomorrow and check the brakes but it doesn't make noise when actually using them. 

[nipper]

Im thinking a brake pad. The brake wear indicator doesnt make noise then the brakes are applied. It is possible that the wear indicator to make noises at odd times when it is just starting to make contact with the disc. The wheel bearings and rotors do flex a tiny bit normally as part of the nature of the parts, so it may very well be as simple as a brake pad issue.

[nmos]

I pulled the front brake pads and there wasn't any sign of trouble there (some life left in the pads and the rotors are smooth) but I went ahead and replaced the pads anyway since I had them off but nothing has changed. 

 

My next two guesses are either a wheel bearing or (hopefully not) the clutch although it isn't slipping at all.  The only time I've had a wheel bearing go (on a Ford Explorer) it did sound a bit similar but It was only noticeable at high speed in a turn (freeway off ramp)  and in this case is in a straight line and at low speed.  Would this be typical on a Subie with 200K?

 

Any other ideas?

[nipper]

It can be a wheel vearing starting to go, at this mileage you are over due. When they first start they like to tease you a bit. Throw-out Bearings are fairly consistant on when they make noises. You can try spinning the wheel and listening with a stethescope to the hub or wait it out to get more pronounced. Luckily as long as your not planning a long trip, the weather is getting nicer so waiting it out a bit may have an up side.

[nmos]

Since my last post I ended up taking it to a couple of shops for an opinion and both agreed that it's "somewhere in the transmission" but couldn't be more specific even using a stethoscope.  This is a 5 speed manual btw.  The second shop is a local place that specializes in transmissions and they are in the process of pulling the transmission for inspection but acording to them the fluid looked good.  Even these folks seem to lean toward replacing it rather than repairing.   Is this really really a more reasonable way to go vs finding the bad bearing and replacing just the bad part?  Are there any particular bearings  that tend to go bad on these and if so how hard are they to deal with?

[HowarD1]

I just bought a '97 Legacy Sedan with an automatic transmission and 90k miles on it. I am having a very similar issue. I am hearing a high pitched whine similar to a midrange note on a flute when the car is moving in reverse. I will have it on jack stands next week with a stethoscope. I will post back with more info. Interestingly enough, I also have a leak in the power steering near the steering box.