Knocking sound from behind dash...
08-23-04, 01:03 PM
#1
Locust of the apocalypse
Thread Starter
Join Date: Apr 2003
Location: Directly above the center of the earth (York, PA)
Posts: 2,553
Likes: 0
Received 1 Like
on
1 Post
Knocking sound from behind dash...
I have a freakin knocking sound that is driving me nuts...
Sounds like somone hitting a half a coconut shell with a rubber mallet.
Its tied to the RPMS (ie it gets faster as RPM rises) and if you sit in the drivers seat, it sounds like its comming from behind the gauges, but if you put yer beak under the dash, then it sounds like its comming from the floorboards..
Pushing the clutch in or out or putting it in gear and pulling out make no difference, its still there just the same as if you were idling in neutral. Heavy load, no load, still there. It gets so fast (and the car so loud) that you can't hear it past 3K in first gear.
I rebuilt the motor and its running strong, however, I did use banzai Racing urethane mounts, which vibrate a bit more.
Can't find anything loose in the engine bay, can't think that the tac would make that much racket... If it was the pilot bearing (which i changed) it wouldn't do it with the clutch out and the car moving..., the throw out bearing is new as well, but again, it doesn't make any difference whethere you have the cllutch in or out. I checked the FMIC, doesn;t seem to be hitting anything
And its not the short shifter rattle.... i have that too, but thats intermittant and much quieter.
Anybody elsa have this noise???????
Sounds like somone hitting a half a coconut shell with a rubber mallet.
Its tied to the RPMS (ie it gets faster as RPM rises) and if you sit in the drivers seat, it sounds like its comming from behind the gauges, but if you put yer beak under the dash, then it sounds like its comming from the floorboards..
Pushing the clutch in or out or putting it in gear and pulling out make no difference, its still there just the same as if you were idling in neutral. Heavy load, no load, still there. It gets so fast (and the car so loud) that you can't hear it past 3K in first gear.
I rebuilt the motor and its running strong, however, I did use banzai Racing urethane mounts, which vibrate a bit more.
Can't find anything loose in the engine bay, can't think that the tac would make that much racket... If it was the pilot bearing (which i changed) it wouldn't do it with the clutch out and the car moving..., the throw out bearing is new as well, but again, it doesn't make any difference whethere you have the cllutch in or out. I checked the FMIC, doesn;t seem to be hitting anything
And its not the short shifter rattle.... i have that too, but thats intermittant and much quieter.
Anybody elsa have this noise???????
08-23-04, 10:48 PM
#3
Banned. I got OWNED!!!
Originally Posted by WAYNE88N/A
Somebody playing a joke on you and wrapped a tie-wrap or something around the driveshaft?
08-24-04, 06:01 AM
#4
RX-7 Alumni
Knock Contol Box
Isn't the knock control box back there?
jk--couldn't resist. But I know your pain, I'm tracing down a funky noise in my FB that's driving me nuts.
Btw, finally installed the FCD and it works great (Thanks again).
Scott
jk--couldn't resist. But I know your pain, I'm tracing down a funky noise in my FB that's driving me nuts.
Btw, finally installed the FCD and it works great (Thanks again).
Scott
08-24-04, 06:26 AM
#5
XBL** Ownicus
iTrader: (2)
Join Date: Mar 2004
Location: St. Paul, Minnnesota
Posts: 1,529
Likes: 0
Received 0 Likes
on
0 Posts
Hmmmm, I have something like that, but it doesn't sound like a coconut. It's more of a metallic ping every once and awhile, and it's coming from this little box on the upper driver's side firewall. It's about 6-8" jutting out of the firewall and to teh right of the brake master cylinder (when looking at the firewall from the engine bay). I have no idea what that component does, but it is damn annoying. 
08-25-04, 08:44 AM
#6
Locust of the apocalypse
Thread Starter
Join Date: Apr 2003
Location: Directly above the center of the earth (York, PA)
Posts: 2,553
Likes: 0
Received 1 Like
on
1 Post
Originally Posted by WAYNE88N/A
Somebody playing a joke on you and wrapped a tie-wrap or something around the driveshaft?
I'm going to adjust the banzai poly motor mounts a bit softer and see if the noise changes.... if it does, i'm switching over to the mazdatrix competition mounts and well see how they work since i have their comp tranny mounts.
Trending Topics
08-25-04, 01:38 PM
#10
Locust of the apocalypse
Thread Starter
Join Date: Apr 2003
Location: Directly above the center of the earth (York, PA)
Posts: 2,553
Likes: 0
Received 1 Like
on
1 Post
Its not a tic, metallic or electric sound, its deeper than that and more of a knock than a tic.. might investigate the Fresh air door though, but its definately sourced from engine vibration cause it NEVER misses a beat at idle... never. its ALWAYS knocking....
08-25-04, 02:31 PM
#12
Seduced by the DARK SIDE
Join Date: Apr 2001
Location: Orange Park FL (near Jax)
Posts: 7,323
Likes: 0
Received 2 Likes
on
2 Posts
I almost didn't catch a bad T/O bearing that would have sounded like that.
The contact ring was not concentric with the guide sleeve.
That would make the bearing want to wobble & knock on the guide sleeve.
The contact ring was not concentric with the guide sleeve.
That would make the bearing want to wobble & knock on the guide sleeve.
Thread
Thread Starter
Forum
Replies
Last Post
