Front end "snap" in 1991 Honda Accord EX with manual transmission

Hi everyone...

As I usually do when seaking solutions, I searched the archives in this
group for similar threads. While I found a few which were similar,
none seemed to be the exact symptoms I'm getting... So here goes...

My 1991 Accord EX Wagon 5 speed has a hard metalic "rap" or "snap" in
(which sounds to be) around the front passenger side wheel. (It may be
under the hood toward that side).

The sound generates generally under acceleration or deceleration, even
if it is slight. My best guess is that it's coming from a "mass
shift".

There is a really great independent Honda garage here in Boulder
Colorado who looked at it a couple of times. I can demo the sound for
them when we go for a test drive, but the mechanics can not recreate
the sound on the rack. (Adding to my belief the sound has something to
do with a change in velocity of some "loose mass".) The shop admits to
being stumped and are honest enough to not suggest they simply begin
replacing parts until they get lucky.

It does not matter if the car is cornering or not. I have even
repacked the CV joints to eliminate the possibility of a bad joint...
but it did not affect the sound.

I can recreate the sound by letting the car back down a very slight
incline, then slightly (or quickly) accelerating forward. I can also
create it by letting the car roll forward slowly (or quickly) and
applying either the normal brakes, or the rear emergency brakes.

I can also recreate the sound by rolling slowly along the street and
slightly accelerating, or decelerating.

Here's the weird "kicker"... The sound disappears as cold and rainy
weather rolls in during the fall and early winter! After a few days of
cold rainy weather, the sound gets quieter and quieter.... and finally
completely disappears until Spring! Just for the record, the car is
parked every night in my garage, with is always a few degress above
freezing.

The car is still making noise this Autumn, because we have had
beautiful warm 75 degree days so far... But just like the past 4
years, I am certain the noise will go away and make no more noise until
Spring, once we get a few cold rainy/snowy days... Then it will
reappear in the Spring.

The seasonal "appearance" and "disappearance" of the sound makes me
think it could have something to do with the viscosity of a lubricant
in some part (lubricant gets thick in winter and thins out again in the
spring.) ... Or it could be a rubber bushing at fault which gets
"stiff" in the winter and "spoungy" again when the warmer weather of
the spring returns.

Any ideas? Has anyone experienced the same thing? The sound is not
only very irritating, but gives me "safefy concerns" as well.

The car has "only" 140k miles on it and is otherwise in above average
condition.

Many thanks!

--- RJ

 

Oh man this is a good one. I am not the most experienced
bird here but having recently rebuilt one heckuva lot of my
own 91 Civic's suspension, I'd go prowling around and poking
at the following, in no particular order:

--Broken front suspension springs. They tend to break at the
top or bottom, and it won't be obvious. IIRC the rubber
molded cap at the bottom can become worn with age, too.

-- Stabilizer bar links (they rust away really well after 15
years! Fortunately, they are easy to replace). They have a
lot of little bushings associated with them.

-- Radius rod bushings too old and fatigued to take load
properly (never heard of those causing problems, but they do
take a lot of force upon braking)

-- Lower control arm bushings. Get under the car (without it
jacked up and then with it jacked up) and inspect for
cracks, how the car sits with them. You can also measure the
height of the upper wheel well on both sides and possibly
get more ideas on the condition of these bushings.

Yabut it has a lot of winter driving on it, no?

 

Hi Elle,

Thanks for the quick reply, Elle.

I forgot to add to the original thread that I already replaced the
stabilizer bar bushings (which you mentioned)... You are right, they
tend to self-destruct for no good reason at all after 15 years or so
(smile). They were making noise (before repair), but it was their own
noise, unrelated to the problem noise discussed here.

I'll take your advice and look as closely as I can at the front
suspension springs, radius rod bushings, and lower control arm
bushings. I've pried like crazy on all those things with a crow bar,
but can never get a peep out of them while the car is sitting still.
.... But they are still under suspect. Everything is "guilty until
proven innocent". ;-) I suspect the radius rod bushing are not the
culprit, as "heavy breaking" is not necessary to produce the sound...
Just gentle acceleration/deceleration will do it.

In particular, I'll look closely at the front suspension springs, as
the sound has a real "under tension" kind of "snap" to it when it
happens. That is, it sounds like a lot of pressure is involved when
the part slips. One thing which makes me think it might not be the
springs is that going over a speed bump (at any speed) does not seem to
trigger the sound. There generally has to be some slight acceleration
or deceleration to trigger it.

One last thought which I didn't mention is that the engine does not
have to be running, nor does the car need to be in gear for the sound
to happen... I can create the sound just by coasting and applying the
brakes (with the engine off.)

I'm willing to entertain any one else's ideas as well... So keep those
cards and letters coming. ;-)

Thanks again, Elle...

RJ (Guangzhou)

 

Motor mounts?
There are 4 if I remember correctly...

 

| engine does not
| have to be running, nor does the car need to be in gear for the sound
| to happen... I can create the sound just by coasting and applying the
| brakes (with the engine off.)

Wheel bearing needs more lubricant, like my '90 accord's
rear left wheel's. Grease is not as slippery as synthetic oil /
fullerene, use the most slippery lubricant available.

 

Yep, that's where I would look first...

JT

 

Hi JT

I've already looked at the motor mounts the best I could... The front
one is easy to see and reach... It appears to be ok. The back one is
a large "complex looking" unit almost impossible to get at easily for a
good inspection.

Using a line-of-sight viewing and a mirror on a stick, I don't see any
damage to the rear mount.

I guess I could tape a microphone to it, run the mike cable to a
headset inside the car, then listen to see if it seems to be the source
of the noise. That technique might not be a bad thing to do with the
control arms, etc. either. The noise should be much louder (in theory)
once I mike the "culprit" component.

Thanks for your input,

RJ

 

My guess is based on your statement that the noise "goes away" during
the winter months which might indicate lubrication being supplied by wet
roads etc. Other than that, I would look to slop in the tranny...

JT

 

You would have to be really grasping at straws to try this. Surprised
Chea didn't blame this on the electric clock.

 

Hi Gordon,

Thanks for your take on things...

Well... The problem might become moot until Spring (or until we have
another few warm days). The temperature here dropped to the lower 20's
(F) last night... When I pulled out of the garage this morning, I was
still getting that noisy "metalic snap"... but within 15 minutes of
driving, right on cue, the noise faded away to nothing. (As I said
early on, the cold weather makes the noise stop.) I've driven the car
several times again today and the noise is gone for now. (It's still
cold outside.) ... But I know as sure as Dick Cheney likes to shoot
his friends in the face that the sound will return when warm weather
returns.

Although it was cold this morning, it was a bright and sunny day, so
the "miracle cure" had nothing to do with the roads being wet (no
lubrication effect from water being sprayed under the car was in play).

Your idea that it could be a wheel bearing may have some merit... Of
course, until the noise returns (along with the warmer weather), I have
no way to test the theory, as there is no noise now that the weather
has turned colder.

Bottom line... I'm back to where I started. :-(

RJ

 

Actually, that isn't my idea and I don't think it has much merit. I
am more inclined to the broken spring or motor mount theory, although
the temperature factor is puzzling.