New mufflers makes my car whistle

kiwikidd77, Mar 26, 8:00am
Just had 2 new mufflers fitted to my Diahatsu Mira LX. The price was OK but now when driving it makes a kind of whistling noise when you get over 50k/ph. It stops when decelerating otherwise there most of the time.
It's going back to the garage where the work was done on Monday so they can sort it out.
I wondered if its because they haven't allowed any movement in the rear muffler its welded solid to the car. I my memory they usually have some kind of flexible join to allow for movement, expansion and contraction.

biggal, Mar 26, 9:44am
What tune does it whistle! Anything catchy!

johnf_456, Mar 26, 9:59am
^ Could be something that makes the car more appealing over a standard small engine sound.

jason18, Mar 26, 6:14pm
Might be a leak somewhere.

intrade, Mar 26, 8:36pm
no a whistel works in a way you blow air thru it and it has 1 real real narrow point where air passes. thats how awistel works. and that will be how your muffler now works. some moron weldedyour mufler almosz shut at 1 point. or the muffler it self is like this.
quote:
It stops when decelerating otherwise there most of the time. end quote
this is because your engines fuems are trapped and get forced back up in to the engine stalling it by flooding back in to the exhoust valve with no oxygen for further combustion. when you have morerevs then it has enough force to blow it passt the wistle restrictor.

intrade, Mar 26, 8:46pm
it is quite normal for cars not to have a flex joint if they have a muvable part where it goes in to manifold.needs loads of rubber hangers to absorb the more shaking . newer cars have a flex joint to ease the shaking on the rubbers.
you can always fit or not fit this flex joint cost of the joint is 80 to 180$ just for the part. In a car that has no much value like my oldtoyota that is gone to the crusher i have had welded a solide part in place of the flex joint . disatvantage is the muffler at timesknocked against the car body . and over longer period the muffler could have had stress fractures from the shaking as it was not designed to not have the joint. It had rusted away before that has happened.

jrlaw, Mar 27, 1:11am
Years ago I fitted a new muffler to a Vauxhall. it whistled. Took it of and changed the muffler end to end and it stopped the noise. Looking down some mufflers the press out in the inner tube has holes that need to be fitted with the holes are towards the out take ( rear).Maybe this is what has happened to your car.

clark20, Mar 27, 10:02am
We had a few first gen Previas and they all started to whistle from 100,000km on. We replaced one with a EVO5 muffler but it was too boomy, shame cause it went better.

pollymay, Mar 27, 11:27am
http://www.youtube.com/watch!v=Nnzw_i4YmKk

The whistle tips go wooWOOOOOO!

tekno23, Mar 27, 4:14pm
But thats only in the mornin,

kiwikidd77, Mar 27, 7:00pm
Thanks for your input people its appreciated. will report back as to what they do about it.

saki, Mar 28, 3:00am
You say that the muffler is welded direct to the body, surely they must have the nouse to mount the muffler by its correct hangers and mounts

rlnhrd, Mar 28, 8:40am
muffler is too small

kiwikidd77, Sep 8, 3:55am
OK took it back today and they reckon the front muffler is a dud so are going to replace it.