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Tapping sound in the rear of the motor

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Old Nov 2, 2011 | 06:07 PM
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Tapping sound in the rear of the motor

I have a knocking or tapping sound coming from the rear of the engine. Can't figure it out. The engine runs good and no check engine light or smoke
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Old Nov 2, 2011 | 06:22 PM
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Is it an FC or an FD? What year? It could just be broken apex seals hitting the rotor housing? Or it could be detonation caused be a bad fuel mixture which could be caused by dying fuel injectors... How many miles on the FC/FD and when was the last engine refresh and are you still running OEM fuel injectors/pumps?
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Old Nov 2, 2011 | 07:13 PM
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exhaust leak? bad bearing?
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Old Nov 2, 2011 | 07:52 PM
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Sorry. I write this thread on my phone. It's an fd 94 but the motor was off a 93 rebuild about 36000 miles on it, at least what I remember. I just check the compression and it's good. I also bought a stethoscope and it sound like it coming from from the tranny close to the bell housing. It's starting to get too dark and I can't really work on it today. Thank you for the brainstorming Einheri
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Old Nov 2, 2011 | 07:58 PM
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I put sealer on the exhaust gasket and I don't really think it's coming from any that. The car runs smooth besides that loud tapping noise
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Old Nov 2, 2011 | 08:00 PM
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Does the sound change when the motor drives power to the wheels?
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Old Nov 3, 2011 | 08:45 AM
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Pilot bearing was either not installed, or is bad.
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Old Nov 3, 2011 | 09:54 AM
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The pilot bearing new. But I did notice that the input shaft from the transmission had worn groves. Could that be a problem? I didn't test drive it yet. It's sitting on four jacks so I wouldn't know how it would sound with power to the wheels
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Old Nov 3, 2011 | 02:47 PM
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When you say pilot bearing new, did you just installed it? Double check your work if so.

-AzEKnightz
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Old Nov 6, 2011 | 09:39 PM
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Check out this video on YouTube:

http://www.youtube.com/watch?v=Sm_-u...e_gdata_player
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Old Nov 6, 2011 | 09:48 PM
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By the way! That's my second time starting the motor on this video. It doesnt smoke anymore. So no oil leaks or blown seals.
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Old Nov 6, 2011 | 10:02 PM
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Lol! AzEKnightz this is my third time replacing a clutch/ flywheel/ pilot bearing on an fd. I check it very carefully before I put in... ( and that's what she said j/k) with also the seal. I took my time on it.
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Old Nov 7, 2011 | 01:38 AM
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Cracked exhaust manifold or something downstream?

It's the only thing I can think of that explains why the tone of the noise doesn't change when you rev the engine.

PS: Hold on, is the PPF bolted securely?

Last edited by NeoTuri; Nov 7, 2011 at 01:41 AM.
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Old Nov 7, 2011 | 01:51 AM
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is it possible to jack the car up and put it on 4 jack stands. And have some body get under neath but stay away from anything spinning and listen to the noise? That way you can pinpoint the noise. Or bring it to a shop.

-AzEKnightz
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Old Nov 7, 2011 | 12:13 PM
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No want to work on rotaries in Fresno area and plus I have too much pride. I got it on 4 jacks. All I really wanna know that it's not a spun bearing or the motor. So that cool. Ima work on it after work, I'm thinking it's something with the tranny.
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Old Nov 7, 2011 | 12:50 PM
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sounds clutch related, something grinding down on the bellhousing of the tranny or throwout bearing munched.

does it change at all when you put it in gear or press the clutch?
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Old Nov 7, 2011 | 09:02 PM
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Karack is the winner!! the throwout bearing did not wanna to snap into the ring! Thank you everyone else for your time and help!!! now its time to paint the door and trunk jams and do the body work, so I could finish my spirit r replica! I love being a body man for these reasons!!
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Old Nov 8, 2011 | 01:35 PM
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Sounds like an attaching bolt came loose from one of the turbos.
Most likely #1 turbo as this had happened to me an another FD.
That sound is the exhaust shooting through a 8mm hole.

Use a hose to the ear to isolate the noise.
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Old Nov 8, 2011 | 07:27 PM
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Thanks cewrx7r1! But, it's already fixed! Snap in ring did not go into the throw out bearing. Everythings seem to be working run. Just a little oil leaking out of the 2nd turbos return line but that easy to fix.
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