Jump to content
CaddyInfo Cadillac Forum

Annoying sound source finally found


Recommended Posts

I have had this really annoying sound for years. It was a tapping/knocking sound only manifesting itself with the engine warm and only at idle and after about 1 minute of idle too. It originated from somewhere at the front of the engine area. I found out that the sound disappeared with the AC-compressor off and thought it was the problem until I discovered that it returned with vehicle in gear. Even with the AC off! Ok, so now what? I checked the accessories and everything seemed just fine except from perhaps a small axial play in the AC-compressor bearings but I was almost certain that the AC was fine. I tried to listen with a stethoscope and tried from underneath but could not locate the sound at all. Finally I came to the conclusion that there has to be something vibrating, like the engine oil cooler line, a loose fan shroud or something like that. The sound was usually gone when I put the car on a jack to add to the complexity. The sound did not get progressively worse and could be gone for weeks so I was certain that it really wasn't anything mechanical. This kept on going and was extremely annoying and slightly embarrassing because I always do all the work on my car (I have only visited repair shops twice since 1992). The other day I had to replace the left rear brake line and after the test drive I noticed that the sound was gone! I guess that one of the brake lines were close enough to the sub-frame to make contact with the right amount of heat and vibrations. Now I can finally get some peace ;)

Link to comment
Share on other sites


It is usually only we, the owners and enthusiasts, who notices the strange sounds and feelings. It's always like this:

"Wait, what was that sound"

"What sound? I can't hear anything unusual"

"That knocking sound"

"Aren't they supposed to sound like that?" :wacko:

Link to comment
Share on other sites

It is usually only we, the owners and enthusiasts, who notices the strange sounds and feelings. It's always like this:

"Wait, what was that sound"

"What sound? I can't hear anything unusual"

"That knocking sound"

"Aren't they supposed to sound like that?" :wacko:

That sounds just about right.... LOL

Posted Image
Link to comment
Share on other sites

I had the same problem with my 87 442 and I finally figured out it was the rubber bumper stop under the hood near the cowl. I thought it was in the dash the whole time.. :blink:

1355177301_Caddy2.thumb.jpg.40dfc05e0861db8b3e74deec4f75cc76.jpg

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...