944 S2 Momentary Vibration/Rattle from Engine Bay on Acceleration?
#16
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As far as I know, I tensioned both belts to the "ideal" settings using the Arnnworx P920X taking care to snap the gauge repeatedly for an accurate reading. I'm not getting any other vibration from the engine except for this momentary "scraping" sound.
#17
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If it were me, since the noise is coming from the front, I'd pull the covers off to double check everything and to make sure nothing's come loose that shouldn't have, e.g. a roller is coming loose (I'm not saying it is likely, just that I'd stay awake thinking about the possibility until i'd checked it.)
#19
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But maybe it is a heat shield somewhere? The one over the cat maybe?
#20
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I find it hard to believe that tensioning the belt to the ideal setting with the Arnnworx tool I'd be worse off than by setting the tension by feel like most people do with the balance belt, but I guess it's a possibility.
The sound is just too metallic to make me think of a belt. I also conscientiously tightened each idler, roller and sprocket to 45 Nm with a torque wrench.
#21
The balance shafts do not remove completely all the engine vibration it just suppresses them. Some vibration modes do eventually cause some rattles as the car milages increases as car bits loosen up. I have driven my car without the balance shaft belt connected at the engine feels quite buzzy. If I drive it like that lots of rattles will appear in time. I get even worse results if the shafts are not alligned correctly. Also I expect the balance shafts are less effective on the S2 3.0 liter engine then on the standard 2.5 liter engine because of the extra capacity.
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Really? There's a guy in the 968 forum who just found out he had no balance belt on his car and he could never tell from driving it.
I find it hard to believe that tensioning the belt to the ideal setting with the Arnnworx tool I'd be worse off than by setting the tension by feel like most people do with the balance belt, but I guess it's a possibility.
The sound is just too metallic to make me think of a belt. I also conscientiously tightened each idler, roller and sprocket to 45 Nm with a torque wrench.
I find it hard to believe that tensioning the belt to the ideal setting with the Arnnworx tool I'd be worse off than by setting the tension by feel like most people do with the balance belt, but I guess it's a possibility.
The sound is just too metallic to make me think of a belt. I also conscientiously tightened each idler, roller and sprocket to 45 Nm with a torque wrench.