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rattle or slight knocking noise in engine

11251 Views 14 Replies 8 Participants Last post by  Leeann_93
Now that i have the brakes fixed i'm gonna move on to the next problem. I have a noise in the engine area that i can only hear at or around 1500 rpms thru the 2000 rpm range. It sounds like a piston rattle but only at those rpms. When it gets above 2500 rpms it dosent rattle anymore and it dosent rattle at idle either,dosent rattle at start-up. i dont think this is doing any damage to the engine ,there is no metal in oil . just wondering if anyone has had this problem or has herd of this problem. I read somewhere the flywheel might be cracked or it might be the torque converter, i just dont know . I thought i might try to get some of these problems taken care of while everything is slow and i had some extra time. :shrug:
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I suspect I have this same issue with my '95. I checked out the bottom end when I had the oil pan off, and everything checked out fine, but I can't seem to narrow down the specific location of the rattling as it sounds like it coming from inside the engine. It doesn't seem to be coming from one side more than the other, but my hunch was on the driver's side based on what I'm hearing in the driver's seat (which I know isn't always 100% reliable for diagnosing). I suspected a stretched timing chain or possibly a loose rocker arm, but the engine has only 95K on it, so that would be a bit early for a stretched timing chain IMO.

Is there a way to check the balance shaft for excessive play with the timing cover removed? The FSM simply tells you how to remove it and install a new balance shaft and the bearing at the rear of the block, not how to check for excessive wear. :think:

Now I'm curious how much vibration the balance shaft dampens out... :think:
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