Front suspension noise W123

[NH82W123]

Hi all,

Getting a muffled "crack" noise from the front left (almost seems to be under the pedals) in the following situations:

1. Just as the engine turns over at starting
2. Just as the engine shuts off
3. When steering into a moderate or tight turn
4. When coming to a stop (more pronounced when abrupt stop)

Does NOT happen:

1. When driving over uneven pavement (unless in a turn as in #3 above)
2. When bounce-testing the front corner of the car like to test the shocks, which seem to be fine

I just had the upper control arm replaced due to uneven tire wear, but that didn't do anything for the noise. I've not observed any other deteriorated bushings on any of the components. Any ideas what it could be?

Thanks all,

Charlie

[OlBrenner]

All suspension joints are suspect but might be worth a look at the motor mount shock. Should only take 10 minutes at the most to get it out and see how it functions. Otherwise you're on a clunk/creak/squeak/shimmy hunt which usually ends in throwing parts at it until it stops. The good thing is these cars usually NEED the entire front end replaced anyway after a certain number of miles and years. Just be sure you use good quality suspension parts such as Lemforder (spelling?), Febi/Bilstein or Meyle. Stay away from the eBay bundles, they're german made (they say) but are of poor quality. Also when you did the upper control arms did you be sure to tighten the body to bushing bolt when the car was sitting on it's own weight to make sure it isn't preloaded?

[patbob]

Normally a turn-replated noise is a bearing or something, but since it also happens when not moving, it can't be that. Startup and shutdown seem to cause the most violent engine shaking but little suspension movement. The noise only when turning, but not road roughness related, makes me wonder if the engine could be bumping into into something. So, check the motor mounts too, maybe one is well worn out.

[NH82W123]

OlBrenner, I actually had my indy do the UCA replacment. (Wish I had the skills/tools to do this myself.) But I did confirm that the body-to-bushing bolt was good and tight.

Patbob, I'll double check the mounts. I asked my indy to check the mounts and all suspension compontents when the car was in for some work after winter storage and all was fine then... but who knows.

Thanks to you both for your replies.

Charlie

[rrgrassi]

Mine made noise like that also. Replaced the engine mounts and engine shocks. All is good. Also check the air cleaner mounts.

[carnut]

Check the steering gear box to frame rail bolts. A rather remote possibility but easy to check.

[ascalise]

guide rod mounts

[NH82W123]

I had the car in for a new starter and asked my indy to check this out. Turns out it's the exhaust pipe not quite lined up with the rubber stop that's just under the driver's footwell. (The PO had the entire exhaust system replaced about a year before I got the car, and apparently the shop that did the work didn't do a great job lining up the parts during installation.)

My indy said it wouldn't be a big job to loosen up the exhaust parts and rotate them back into the proper position when the car's on a lift, but after having just spent a small fortune for a new starter I decided to put it off this visit.

Any idea if this would be an approachable DIY project with ramps/jack stands?

Charlie

[Johnson Chan]

Originally Posted by ascalise

guide rod mounts

I second that. This goes with the clunk when braking or coming to a stop.