exhaust vibration

[LTUDSM]

hey guys i would like to know does anybody have a vibration from a turboback 3' exhaust??
my whole interior is shaking like crazy,and its so damn annoying.Is that supposed to be like that or its something wrong??

 

[romeen]

You can try checking for torn exhaust hangers. But I've never heard of an exhaust system causing the kinds of vibrations that you are describing. I would think the vibrations are coming from the motor itself. Maybe a problem with motor mounts or harmonic balancer.
Is the vibration present only in a certain rpm range or all the time?

 

[LTUDSM]

You can try checking for torn exhaust hangers. But I've never heard of an exhaust system causing the kinds of vibrations that you are describing. I would think the vibrations are coming from the motor itself. Maybe a problem with motor mounts or harmonic balancer.
Is the vibration present only in a certain rpm range or all the time?

i changes my motor mounts and harmonic balancer 3 months ago i thought that the vibration cause was motor mounts ,but when i change them still the same thing .and vibration presents all the time ,and its so damn loud inside the car i dunno could it be problem of exhaust pipe been very close to the bottom of the car??

 

[LordZed]

Is it noise resonance? Not a metal vibration per say but sound vibration…like if you had a sub hitting base in your car?
I assume you mean the latter. The 3” is going to be louder and depending on your muffler you could get fairly high interior volume. These car’s are hatchbacks so it’s easier for noise to make it to the inside. I don’t have a good exhaust on my car yet but it does have a flowmaster muffler. I can’t hear it inside the car very much, but from inside my house when it’s at idle there a low droning bass from the exhaust. Take a ride in a Fox body Mustang with 3” Flowmasters and your car will seam live a sanctuary. Loudest car I’ve ridden in hands down as far as interior resonation!

 

[romeen]

i changes my motor mounts and harmonic balancer 3 months ago i thought that the vibration cause was motor mounts ,but when i change them still the same thing .and vibration presents all the time ,and its so damn loud inside the car i dunno could it be problem of exhaust pipe been very close to the bottom of the car??

Have you tried getting under the car while it is running to see if any portion of the exhaust is actually hitting the underbody? Maybe even moving it back and forth by hand with engine off might reveal possible contact points or you could visually examine for any scuffed or worn areas. If you're confident that the problem is originating from your exhaust and your available space or tools won't allow you to get under the car you might consider having an exhaust shop put it on a lift and look at it. Your description sounds very annoying and it may be worth the expense.

 

[oldman]

Did you replace the mounts with stock or poly mounts?

 

[LTUDSM]

Did you replace the mounts with stock or poly mounts?

the poly ones

 

[oldman]

the poly ones

There's your source of vibrations. Did you change all four mounts? (tranny?)

 

[Apeximprt2nr]

My exhaust creates a loud vibration/ buzzing sound inside my car near the rear hatch.
It may be because 1 hanger on my exhaust isn't fully on, not really sure.

 

[romeen]

I also have polyurethane motor mounts. At normal idle around 750 the vibrations are quite harsh but they disappear at around 950. I have my idle adjusted to around 1000 now and the vibrations are gone.

 

[oldman]

I also have polyurethane motor mounts. At normal idle around 750 the vibrations are quite harsh but they disappear at around 950. I have my idle adjusted to around 1000 now and the vibrations are gone.

1000 is a bit high. My entire interior is falling apart , I'm think about going back to stock since I have AWD.

 

[romeen]

1000 is a bit high. My entire interior is falling apart , I'm think about going back to stock since I have AWD.

Now that you bring it up, is it potentially harmful to the engine to run my idle that high?

 

[oldman]

Now that you bring it up, is it potentially harmful to the engine to run my idle that high?

Beside wasting gas and not able to pass inspection, your ISC is probably driven out of its range leading to idle surge, unless you're able to change the idle speed via eprom or link.