DIY: Fixing exhaust squeak at idle 2014-2015

[Daox]

So, for nearly the entire time I've had my 2014 Mirage, I've had an intermittent squeak at idle. I figured it was just a loose accessory belt, so when I had a chance, I tightened it up. That did absolutely nothing. So, I got myself a new belt. That also did absolutely nothing. At this point, I figured it may be a bad bearing in the A/C compressor or water pump and I didn't feel like fixing that.

Fast forward a while, and the squeaking has gotten worse. It now is a continuous squeak at idle. So, a bit more investigation was done. I put the car up on ramps, and got under it to see where it was coming from. Here is what I found.




So, the exhaust was squeaking. The movement of the engine at idle moves the exhaust back and forth and it squeaks. I decided to fix this today.

To do this, I had to remove the catalytic converter. There are two bolts with springs on them at the back side.





The next step is to remove the CV joint heat shield. This one is a little tricky. One bolt is readily accessible, but the other is above the shield and you pretty much need a flexible socket joint to get at it. Here is a bad picture that shows the two bolts.







There are also two bolts with springs holding the CAT to the manifold. Again, that flexible socket joint will really help you here.







You will also have to unplug the oxygen sensor.





With all the bolts out, I pulled the rubber exhaust hanger off of the chassis hook to drop the rear exhaust down and out of the way. This allows you to pull the CAT section out.





Here is the front of the CAT section. You can see it seems that it has been rubbing since its got shiny metal vs dull or rusty metal.





The back side didn't seem to have any noticeable rubbing marks on it.





My solution to this issue is to try and put a coat of anti-seize on the joint. This will lubricate it and stop it from squeaking. I'm not sure how long it will last, but anti-seize is made to handle high heat, so I hope that it'll hold up for a while. My other option I was thinking of was brake caliper pin lubricant, but I wasn't sure it was safe for oxygen sensors and CATs...





I also put some anti-seize on the back. I figure it can't hurt.





I buttoned things back up in the reverse order. All in all, it was pretty quick and easy.

I do wonder if anyone else has this issue? I found it very annoying as anytime the car would idle, it would squeak.

[Top_Fuel]

I do wonder if anyone else has this issue?

Hmmm...I occasionally have a squeak that sounds similar to that when I first let the clutch out from a dead stop. I assumed it was the throwout bearing or something. But man...it sounds just like that...lol. I wonder if the load of letting the clutch out is causing the exhaust to shift slightly and squeak?

[Cobrajet]

I have a similar squeak, but since I was pretty sure it was benign I never bothered to investigate it. If it starts to drive me nuts, now I know how to fix it. I assume this procedure DID fix it?

[Daox]

Yes, it has totally eliminated the squeak. However, I literally just did it last night. The engine has not gotten fully warmed up since then. I am curious to see how long it lasts. I'll update this thread if it starts squeaking again, but so far it is nice and quiet.

[Cobrajet]

Oddly, mine only squeaks like this when it is cold. How many miles do you have?

If this does not work, you might try something like high-temp silicone RTV sealant in place of the anti-seize.

[Eggman]

Doesn't exhaust temperatures reach into the 1000℉ range? Especially around the catalytic converter assembly. I wonder how long anti-sieze or high temp silicone RTV would last.

[Daox]

If the anti-seize doesn't work, there are other lubricants to try out. Powered graphite is one, but I have my doubts it'll stay in place. My next go to is actually Permatex ceramic extreme brake parts lubricant. I already have some of this stuff sitting on the shelf. I just checked the temperature range, and it says it is good for up to 3000°F! That should handle exhaust temps for sure.

[klroger]

If the anti-seize doesn't work, there are other lubricants to try out. Powered graphite is one, ]

I was a mechanic @ a ford dealer when the Tempo & Escort where introduced & they were blessed with this issue also. We used the powdered graphite with great success on those gems

[Cobrajet]

Doesn't exhaust temperatures reach into the 1000℉ range? Especially around the catalytic converter assembly. I wonder how long anti-sieze or high temp silicone RTV would last.

Temps may get that high right at the manifold, or in high-performance vehicles. Permatex Ultra Copper is rated to 700 degrees, and is recommended for sealing exhaust manifolds and turbochargers.

At 700 degrees, all of your exhaust components would literally be glowing red hot.

[Daox]

Alright, I took the car to church on Sunday and a few errands after. The anti-seize mostly works. On initial startup, it still kind of squeaks. However, after a little bit of driving it doesn't squeak. I'll drive it a bit more before trying something else, but I am not totally satisfied.