Jan Olsson Posted July 15, 2014 Report Share Posted July 15, 2014 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 More sharing options...
rockfangd Posted July 16, 2014 Report Share Posted July 16, 2014 funny ho the simple things will drive us nuts. Glad you found it. GM FAN FOREVER Nice, clean, luxury= fine automobile Link to comment Share on other sites More sharing options...
Jan Olsson Posted July 16, 2014 Author Report Share Posted July 16, 2014 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?" Link to comment Share on other sites More sharing options...
Texas Jim Posted July 16, 2014 Report Share Posted July 16, 2014 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?" That sounds just about right.... LOL Link to comment Share on other sites More sharing options...
jndnaps Posted July 22, 2014 Report Share Posted July 22, 2014 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.. Link to comment Share on other sites More sharing options...
AlpineX3 Posted July 24, 2014 Report Share Posted July 24, 2014 Glad you got it all figured out, I would've gone mad! Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.