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Noise of unknown origin

'94 Plymouth Alliance 3.0. Had a broken engine mount; the current mystery noise was heard among the other sounds made by the broken mount, and the mystery noise was assumed to be caused by the mount. Transaxle was rebuilt (the place is known competent) and mount replaced, but the mystery noise persists.

There isn't anything I can identify the noise with. It's from the front right side of the car, sounds like thick metal parts hitting each other.

Pull down the driveway. Go over the flattened curb section - BONK Turn left - BONK

100 feet to intersection - nothing Turn right - BONK Down street, hit bump - nothing Veer slightly right - BONK Straighten out - nothing Veer slightly left - BONK Straighten out - nothing Stop - nothing Turn right - BONK Steer slightly right and left - nothing Turn left - nothing

Now that it's been driven for a minute or two, it will make the noise less and less in response to slight steering. Normal steering is the most likely thing to get the noise, but not consistently. There is no change whatsoever in steering, road feel, braking, or anything else between noises. Braking of any sort does not seem to cause or prevent the noise.

Accelerate or decelerate during turn - nothing Hit bump - 10% of the time BONK, 90% nothing Hit bump immediately after steering - likely BONK Jackrabbit acceleration - nothing Panic stop - nothing Parked, bounce car up and down - nothing Wobble tire & wheel - no looseness or play New brake pads & rotors - no difference

I haven't found anything I can do to make the noise five times out of ten, nor anything I can avoid doing to prevent the noise five times out of ten. That's why it's so mysterious. Ideas appreciated.

Reply to
clifto
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Check the front swaybar endlinks and frame mounts?

Reply to
Noozer

I've had this type of mystery noise, and in my case it was the front calipers, believe it or not. It was the kind of setup where the piece that takes up the slack between the calipers and the mount could wear, allowing the calipers to wiggle around (as opposed to just sliding in and out).

It didn't make the noise on braking, but on turning. Apparently, when the spindles see more/less stress (turning, bumps) the spindle, and therefore the rotor, would move around just enough to cause a clunk because the caliper wasn't properly floating.

Dave

Reply to
spamTHISbrp

clifto ( snipped-for-privacy@gmail.com) writes: ...

I had a similar noise recently in my Ford Focus. It turned out to be a broken spring, although it was initially diagnosed as a strut bearing. Dan

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Reply to
Dan Beaton

There is an alignment procedure for the motor mounts. If the engine is not in the correct left to right position, an axle could bottom out into the transmission, making the sound you are hearing. I had a Shadow that drove me nuts for almost 3 months before I finally took it in and had it checked out. If I would have bought a book, I'd have known, but I didn't think of the engine alignment.

Reply to
Steve Walker

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