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Discussion Starter #1 (Edited)
Low Compression:
I have low compression in one of my cyliders. All the other three are reading at 180 and the 4th one shows 150. The spark plug is discolored and around 3000+ rpms there seems to be some sort of really fast paced rattling. I have a supercharger on it, but it is most definitely not the supercharger. I can hear the supercharger spool all the way through the rpm range and this noise is separate. I heard it coming from the engine when I was doing a dyno pull. Any thoughts?

Transmission:
Only between 1500 and 2400 rpms do I hear this rattling noise. Also when I was on the dyno, he two of us agreed that it was coming from the tranny. I have a completely stock tranny. It happens at that RPM range in any gear. When I push the clutch in it goes away. The clutch doesn't seem to be slipping at all, and I'm not sure if possibly it could be the gears. Does this sound like a clutch issue?
 

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FF's Quadriplegic!
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You might want to check ALL your sparkplugs and see if they are set to the right height or needing replacing.

That clutch rattle you here is pretty much normal. You should hear mine! When I reset the ECU, the sound goes away, but then it comes back as the ECU learns my driving habits. I haven't had any problems with the rattle as all the gears shift nicely and the car pulls just like it should. This is for over 45K miles so far.
 

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Fins Up!
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yeah i here the same rattle noise in the same rpm range, it has been brought up before and no one ever knows what causes it. but everything works great on my car so i just ignore it and i am hardly down that low in the rpm band any way, lol.
 

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Is your car tuner, The 150 isnt real bad but it does tell there is some compression getting bye either the piston rings or the valves a leak down test will show what one it is

A lot of the Trans make this noise

Tom
 

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Discussion Starter #5
My car is tuned, and I have replaced the spark plugs twice with about 6000 miles on the supercharger.

Would a new clutch, say an aftermarket one still make the same noise?

Would a valve make that real fast pace ticking noise?
 

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To change the clutch could make it less or more noisy hard to say , Yes a valve will make a fast pace ticking noise , Get you a long hose like a garden hose anout 4 to 5 feel long one end to your ear the other places on the engine and see if you can locate where its coming from

Tom
 
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