Loud metallic noise when cold

[ghunt81]

I don't remember my car doing this last year before I put it away for the winter, but on a cold start I get this loud metallic noise from under the car that seems to change slightly with engine speed. It's not quite a "ringing" sound, but sounds like metal on metal. Goes away once the car has been running for a few minutes. Definitely coming from somewhere toward the front of the car.

I fixed the separator plate noise years ago (and even that was only around 3000 RPM), this one is happening at idle. I haven't been under the car yet to look at it. I have aftermarket cats so I don't think it's a cat heat shield but I suppose it could be. Anyone had this happen?

 

[AndrewNagle]

I don't remember my car doing this last year before I put it away for the winter, but on a cold start I get this loud metallic noise from under the car that seems to change slightly with engine speed. It's not quite a "ringing" sound, but sounds like metal on metal. Goes away once the car has been running for a few minutes. Definitely coming from somewhere toward the front of the car.

I fixed the separator plate noise years ago (and even that was only around 3000 RPM), this one is happening at idle. I haven't been under the car yet to look at it. I have aftermarket cats so I don't think it's a cat heat shield but I suppose it could be. Anyone had this happen?

me too I also have after market cats and actually swapped them out thinking that was it and it wasn't

for sure something in the exhaust area

 

[nbk13nw]

I had that same issue when a muffler baffle rotted and came apart.

 

[ghunt81]

Well this one is definitely coming from somewhere around the engine/bellhousing/transmission area. I'll have to do some sleuthing and see if I can find it.

 

[nbk13nw]

Could also be one of the heat shields vibrating against the chassis.

 

[cavero]

Since it's an '05, could it be one of the exhaust hangars they had the TSB for? There were extra hooks on the exhaust right around the transmission cross member that were only there to aid assembly in the factory.

https://www.s197forum.com/threads/crossmember-exhaust-mounts.135100/

https://www.stangnet.com/images/stories/docs/s197_TSBs/08-03-04.pdf

 

[nbk13nw]

Good call. I totally forgot about the hangers

 

[06redgt]

Sounds like the TOB on the slave cylinder. Mine was doing that before I did a 6060 swap. Made more noise in cold weather, and would go away after a few minutes.

 

[Dino Dino Bambino]

You'll need to get the car up on a lift and use a mechanic's stethoscope to localize the noise. Otherwise it's like pissing into a headwind on a dark night.

 

[ghunt81]

Sounds like the TOB on the slave cylinder. Mine was doing that before I did a 6060 swap. Made more noise in cold weather, and would go away after a few minutes.

Unfortunately I'm thinking you may be right here. I noticed it changed a little (not much but a little) with the clutch pedal pushed in vs. out in neutral. Damn.

I did find one of my control arm heat shiels was loose but I don't think that was the culprit. So I might be looking at a clutch job this winter.

 

[rickf]

Mine has done that for 3 years, never got worse or better. I think there was a bulletin about the separator plate between the engine and transmission rubbing the flywheel under just the right conditions. I figure I will find it this summer when I swap out the tranny and put in a new clutch.

 

[ghunt81]

As I said I already fixed the separator plate. When I first got the car it was making this super loud ringing sound around 3000 RPM, it was the separator plate. Wedged some rubber in there using a couple unused threaded bosses on the bottom of the bellhousing and it's been good ever since.

 

[ghunt81]

So after driving the car a few more weeks, I think 06redgt may be right. It changes with the clutch pedal pushed it. Guess I'm gonna be doing a clutch on this car next winter.

 

[Dino Dino Bambino]

If the sound is reduced or eliminated when you depress the clutch pedal, the culprit is the throw out bearing.