is it possible that a valve would have a nasty sound? almost like a spun bearing? my engine makes a "knock/ tap" when the engine is under stress, but not while parked and reving the engine. if i take it to 3k rpms, thats when you hear it, not before, and not after. now, last friday i drove to tennessee, and wednesday i came back. for me thats 494 miles each way, and the thing did awesome. the only time i can really hear it is when i'm in gear at about 3k rpms. if you go out to the hood and try to replicate the noise by pulling the throttle, it doesn't make any noise at all. i'm kind of stuck here, cause i don't know what i'm supposed to be fixing, ya know? lol. could a stuck lifter sound like that? because all the spun bearings i've heard, are a constant knock whether sitting still or driving. thanks guys.

 

I doubt that your problem is crank bearing or valve lash related.
Is this more like a metallic rattle or is this a rhythmic sound? Does this sound appear louder on either side of the compartment?
I think this 'sound' is being transmitted into the passenger compartment thru either a hose, cable or something grounding to the chassis. Reason? You can't hear it 'out in the open'. You need the quiet of the compartment to be able to hear it.

P

 

that gives me something to think about. another thing is, it only makes that noise after the car is warmed up. if its nice tomorrow, i'll see if i can put it up on jack stands, and "drive" it to see if i can hear it from the outside. i mean, it runs fine, drives fine, did good on a 1,000 mile round trip, so i also have doubt that its a bearing, that thing woulda spewed its guts i woulda thought. 8hrs straight 3500 rpms, thats pretty rough on an engine.