My car is so loud inside!

pippo

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People,

1987 sunbird GT NON turbo. Orig owner. The car is now (has become) so loud inside the cab while driving it is unbearable. I measure 87b decibels inside the cab. yes, I bought a decibel meter! Normal decibels are about 70 dec. Muffler shop found no unusual leaks. Tips appreciated as I hate this loud noise.
 

melsg5

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Did anybody at the muffler shop actually drive the car?
 

92 Sunbird LE

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Pull the carpet and insulate the floor with boom mat or spray or roll on bedliner, check windshield for wind leaks, Also check floors, doors, cowl and and firewall for rust out holes.

These cars are real thin to begin with, so noise is a common problem when they get older. ( not insulated from the factory that good either)

I'm used to it in mine......

Doug in P.R.
 

pippo

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Did anybody at the muffler shop actually drive the car?

Good tip, Mel. I should have had them do that! Maybe I can go back and request that.
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pippo

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Pull the carpet and insulate the floor with boom mat or spray or roll on bedliner, check windshield for wind leaks, Also check floors, doors, cowl and and firewall for rust out holes.

These cars are real thin to begin with, so noise is a common problem when they get older. ( not insulated from the factory that good either)

I'm used to it in mine......

Doug in P.R.
Also good idea. i didnt think of that. A thick coating has to help.
 
G

G-154537

People,

1987 sunbird GT NON turbo. Orig owner. The car is now (has become) so loud inside the cab while driving it is unbearable. I measure 87b decibels inside the cab. yes, I bought a decibel meter! Normal decibels are about 70 dec. Muffler shop found no unusual leaks. Tips appreciated as I hate this loud noise.
I really miss my 87 Sunbird GT. Can we see a photo of yours?
 

pippo

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Well, before I smeared black bedliner on surfaces I figured Id try duct taping a leaf blower to the tailpipe, and spray soapy water on exhaust manifold area- donut. and the studs holding manifold to engine. I found 2 leaks at the manifold studs, but learned almost all 7 (one stud is missing) were loose! Donut also formed bubbles. Tightened the 7 studs and no more soap bubbles. Donut 2 studs (theyre new) could not be tightened down anymore- they are maxed out, not sure how to seal up that donut any tighter, but at least I got the 7 studs.

So, does anybody know what size stud/length I should get for the 8th stud on the manifold? Need pitch/diameter. Worst will have to unscrew another adjacent one.
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92 Sunbird LE

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Take off the nuts and add washers , it puts more pressure on the springs to seal it up better. Also apply the high heat orange Permatex to the doughnut gasket before tightening.

So much for the exhaust shop finding leaks, huh ?

Doug in P.R.
 

pippo

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I will try that, Doug. Good tip as always. Right, about the professionals at exhaust shops. Useless.
 

pippo

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So, any idea where I can find the specs for the studs for engine block for our cars? Need pitch and size in mm. And fine or coarse thread? I need just one. Only other way is to remove one in there currently.
 

pippo

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I had some orange high heat permatex in the drawer, and applied it. But while I was putting on the extra washers I dropped one into the exhaust pipe! How dumb! Tried to hook it out with a wire with no luck. Think this will hurt anything? Obstruct any flow?
 

92 Sunbird LE

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Take one off and match it up at ACE hardware, use a bolt and cut off the head, and add a nut and lock washer. Grade 5 or 8 .Its probally metric.

Doug in P.R
 

92 Sunbird LE

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Get one of those extendable magnet pickup tools they sell at the autoparts store. Otherwise the washer make a rattling noise in the convertor. If you cant get it out, no harm will be done.

Doug in P.R.
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