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32valvZ · 12-02-2007

Ok, I have pretty much all the small to medium jobs taken care of since getting my car a couple of weeks ago.......brakes are done, b/u light switch is done, extensive cleaning of the suspension parts done & many other small jobs also.

Now I am on to bigger problems. When sitting still at idle or while moving, clutch in or out........I get a very noticeable vibration at 900-950 rpm.....Thats pretty much the only time I get it.

I spoke to Bill Bordeux via Email & he suggested maybe an injector miss or a weak coil. After I elaborated on a couple of things, his conclusion was "inconclusive"....

I do hear some throw out bearing noise with the clutch out, so I know that will need attention.

The car starts right up, idles smooth when cold or hot, runs strong throughout the rpm range. I have no problem changing gears & the clutch pedal feels "right".

I suspect the flywheel or clutch assembly itself....it feels like an unbalanced tire would feel. Bill said maybe the pilot bushing. I need to add that sometimes when downshifting from 5th to 4th or 5th to 3rd, the pilot bushing will make a sound like rubbing your finger on wet glass.....its very brief & happens exactly when the clutch releases.

Could the vibration be the pilot bushing? Aside from the 900-950 rpm, its as smooth as silk....any ideas or experiences are welcomed.

Sorry for the long post....TIA
John

12-02-2007	#1
32valvZ Join Date: Nov 2007 Location: Sunshine State Posts: 1,061	Vibration concern Ok, I have pretty much all the small to medium jobs taken care of since getting my car a couple of weeks ago.......brakes are done, b/u light switch is done, extensive cleaning of the suspension parts done & many other small jobs also. Now I am on to bigger problems. When sitting still at idle or while moving, clutch in or out........I get a very noticeable vibration at 900-950 rpm.....Thats pretty much the only time I get it. I spoke to Bill Bordeux via Email & he suggested maybe an injector miss or a weak coil. After I elaborated on a couple of things, his conclusion was "inconclusive".... I do hear some throw out bearing noise with the clutch out, so I know that will need attention. The car starts right up, idles smooth when cold or hot, runs strong throughout the rpm range. I have no problem changing gears & the clutch pedal feels "right". I suspect the flywheel or clutch assembly itself....it feels like an unbalanced tire would feel. Bill said maybe the pilot bushing. I need to add that sometimes when downshifting from 5th to 4th or 5th to 3rd, the pilot bushing will make a sound like rubbing your finger on wet glass.....its very brief & happens exactly when the clutch releases. Could the vibration be the pilot bushing? Aside from the 900-950 rpm, its as smooth as silk....any ideas or experiences are welcomed. Sorry for the long post....TIA John