Trying to get an idea of what to look for here. Noticed this began occuring about a week back.

Although I could be wrong, I seriously doubt it is anything wrong with motor. It does not sound like any type of SBC noise I have ever heard and I can still spin to 5500RPM (And have done so about a dozen+ times) without any ill effects or the noise getting any worse. Here's what's going on.

When the engine is FIRST started when COLD, a tapping/knocking noise can be heard from somewhere in the engine bay. The best way to describe it is the valvetrain in an overhead cam engine that is low on oil. The tapping seems completely sporadic/does not exhibit a steady pattern, does not increase (And actually disappears/becomes inaudible) with engine rev and can only be heard for the first 1 - 2 minutes when the engine is freshly cold.

Gonna unhook the radiator fan and start probing things with a stethoscope tomorrow, but just wanted to get an idea on what to zero in on. Thinking it could possibly be a front end accessory. Waterpump only has maybe 2k miles on it but I'm not automatically ruling it out. Never heard of an alternator making this kind of noise, and it doesn't sound like It's coming from there. AFAIK, steering pump is the original with about 170k miles.

 

Have not gotten around to probing yet, however I did discover that the entire hub of the power steering pump has a small amount of in and out play in it. If I grab hold of the pulley and apply a moderate amount of force to it (This would probably be very easy if the belt weren't hooked up), it can be moved in and out and makes a tacking sound each time it does. Is the time of the last front end accessory drawing near?

As a precaution, I am also going to wait for a warmer day and pull my valvecovers and check for any loose rocker arms. Although if it was the rockers wouldn't it make sense for this problem to occur as long as the engine was running? The only thing I can think in terms of this aspect is maybe when the car sits for awhile most of the oil drains off the rockers and off a fresh morning start they're making noise before they get good lubrication?

 

YOu can quickly & easily rule out (or not) the PS pump and other accessories by removing the belt.

If it does turn out to be an accesory, get a piece of heater hose and (I LOVE telling people to do this!!!) STICK IT IN YOUR EAR, and probe around with the other end of it (careful of the fan of course) to find the offender.

 

Yeah I plan on doing that. I actually used the belt method to determine my belt was making a scary sound a week or two ago (Look in aftermarket product review for my post on CRC belt conditioner).

As for the hose in the ear thing, I read that for the first time 2 nights ago and cracked me up. At my job though we have an actual stethoscope and the long slender probing rod it has proves to be quite useful for probing the shaft os both the waterpump and power steering pump even while they're spinning.

 

Forgot to update this thread and let everyone know I figured out the noise was STILL the belt. Why they are making this kind of sound instead of a squeal I have no clue but that CRC stuff really screwed them up. I'm just going to ride them out for another month or two until I get my underdrive pullies.

Do not use CRC belt conditioner!