Strange noise from under vehicle

AlexFourTwenty
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Strange noise from under vehicle

Postby AlexFourTwenty » Wed Nov 29, 2017 11:41 am

this is an ae85 with a 20v svt swap. The noise is like a metallic rattle. It’s repeated so almost like a loose metal line hitting the body or chassis. (Tatatatata) Yet only does it upon deceleration and when I’m coasting in neutral as well. Not while acceleration nor idling stopped. It’s coming from under the car just can’t really pinpoint it. Can this be an unbalanced driveshaft or bad u joints?

totta crolla
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Re: Strange noise from under vehicle

Postby totta crolla » Wed Nov 29, 2017 12:07 pm

Try checking the exhaust.

notnilc20
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Re: Strange noise from under vehicle

Postby notnilc20 » Thu Nov 30, 2017 6:09 pm

Ae85? Sounds like a heat shield....iirc there is one in the rear above muffler, one above the bend over the axle and another one above the catalytic converter......but I'm not familiar with any ae85....

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jondee86
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Re: Strange noise from under vehicle

Postby jondee86 » Sat Dec 02, 2017 5:53 pm

Get under the car and grab the driveshaft with one hand either side of the hanger bearing.
Check for movement up down and from side to side. If the shaft moves around a lot and
easily, you might even be able to get it to "clunk" with a good heave. If it does, then that
means that the rubber support for the bearing has broken down, and you need to replace
the bearing assembly. Looks like this....

Image

If the rubber is quite firm and you can't get much movement in any direction, then statrt
looking elsewhere :)

Cheers... jondee86
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persists in trying to adapt the world to himself. Therefore, all progress
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AlexFourTwenty
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Re: Strange noise from under vehicle

Postby AlexFourTwenty » Sat Dec 02, 2017 8:22 pm

notnilc20 wrote:Ae85? Sounds like a heat shield....iirc there is one in the rear above muffler, one above the bend over the axle and another one above the catalytic converter......but I'm not familiar with any ae85....

It’s the same as ae86 just base model. And no this car has no shields of any kind it’s torn apart lol

AlexFourTwenty
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Re: Strange noise from under vehicle

Postby AlexFourTwenty » Sat Dec 02, 2017 8:24 pm

jondee86 wrote:Get under the car and grab the driveshaft with one hand either side of the hanger bearing.
Check for movement up down and from side to side. If the shaft moves around a lot and
easily, you might even be able to get it to "clunk" with a good heave. If it does, then that
means that the rubber support for the bearing has broken down, and you need to replace
the bearing assembly. Looks like this....

Image

If the rubber is quite firm and you can't get much movement in any direction, then statrt
looking elsewhere :)

Cheers... jondee86


I couldn’t really get good leverage since I only have a scissor jack but I got under and saw marks on the driveshaft well as if the driveshaft has been rubbing in there above the shaft. So I think you may be right with that shaft bearing.

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mad_86
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Re: Strange noise from under vehicle

Postby mad_86 » Sun Dec 03, 2017 6:42 pm

also check driveshaft bolts are nice and tight, at the diff flange

AlexFourTwenty
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Re: Strange noise from under vehicle

Postby AlexFourTwenty » Thu Dec 07, 2017 5:25 am

Finally lifted it and took a look. There are markings of driveshaft scraping the tunnel above it on the chassis. What can this be?

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mad_86
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Re: Strange noise from under vehicle

Postby mad_86 » Thu Dec 07, 2017 10:20 am

Has to be the center bearing like kinder said
See if it moves around , grab the drive shaft move it around with your hands if moves a lot needs to be replaced . It shouldn't have any play