Jump to content
Ultimate Subaru Message Board

94 Legacy Heat shielding question


Recommended Posts

94 Legacy 78,000 mi.

 

I'm getting a vibration at low RPMs from the heat shielding. This happened once before, right before a service call so I let them take care of it then. Now, I have no reason to bring it in, and I'm wondering if it's something I can take care of myself.

 

I have a friend who knows a bit about cars, and he offered to take a look. I'm wondering if there's a site or something that would show exactly where the shielding is located and what specifically would need to be done. Would it be just a matter of tightening something? I've looked around online and couldn't find anything.

 

My apologies if I wasn't technical or precise enough; I'm not too savvy when it comes to this kind of stuff.

 

Thanks in advance.

Link to comment
Share on other sites

There are a couple different shields. The best way to figure out which one it is, is to jack up the car or drive up a set of ramps, and try to wiggle the shield around. Let the car sit so the exhaust isn't hot.

 

Of the exhaust shields on cars of that vintage are probably going to be rusted up, and the clamps really not working anymore. About the only thing that works is to cut them off with a die grinder/dremel or a torch.

Link to comment
Share on other sites

my heat shields are starting to make lots of noise, i just haven't had a chance to crawl under there and figure out exactly which one(s).

 

the heat shields are another layer of metal which is bolted onto the exhaust pipes and around the catalytic converters and resonators. they help stop the transfer of radient heat, so you won't cause a fire when you park over things like grass and leaves.

 

in order to find which ones are rattling, you raise the car and support it with jack stands, then rev the engine to a speed that causes it to resonate (an assistant helps for this, or you can put a wedge at the throttle body to keep it at a high idle. then crawl under and poke at all of the heat shields while wearing a pair of heavy gloves (some areas get really hot). when you touch one and the noise stops, inspect it and see if you can find any loose hardware or cracks. sometimes they can be resecured with large hose clamps, or are more often removed all together. if you go for the later, just be sure that you don't park over anything flammable!

 

good luck

Link to comment
Share on other sites

If you can get under the car, simply use a hammer to tap on the shields to find out which ones rattle - you'll be able to tell by the sound. forward heat shields are usually the culprits, the ones covering the pipes coming of the manifolds and the ones right before the catalytic converter.

 

Solutions: You could have someone "spot weld" the shields to the pipe. Others have stuffed a heat resistant material between the offending shield and pipe (steel wool, bits of steel/stainless scouring pads). On my 96 OB, I used large carpenter nails, driving them between the shield and pipe - 3 years ago and still no rattles....

Or you could simply remove them as Josh suggested.

 

 

Paul

Link to comment
Share on other sites

Here's what happened:

 

My buddy got the car up, slid under the car, and had me rev the engine to the point where the vibrations occurred. He told me that he had the same problem with his Maxima a few couple of years back, and he had just removed the offending part to solve. After I got the engine to the right point, he said vibrations were coming from a couple of different locations. We then switched places so I could see for myself. The vibrations were coming from the middle of the car and the front, near the catalytic converter.

 

First of all, yes, there was plenty of rust along the shielding where the bolts are. I was able to break off some small bits just using my fingers. I suggested we remove the shielding, but he said that the idea of wedging some metal in there sounded like a better idea so that the shielding would stay. Not that I park in tall weeds or anything, but if this idea didn’t work, removing the shielding would always remain an option.

 

So, after the nails got pounded in, we lowered the car and I took it for a spin up and down the street. What a world of difference! Amazing that a few nails could solve this problem!

 

Of course, going under the car I saw that the muffler is going to need replacing within the next year, as a hole looks like its being rusted through. I suppose this is not unusual for a car of this age.

 

In return I helped him bleed the brakes on a ‘71 Camaro he’s rebuilding. A fair enough trade.

 

Thanks to all of you for your suggestions. I certainly now know where to come for future questions on my Subaru!

 

 

 

:headbang:

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.

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.

 Share

×
×
  • Create New...