Engine Strange Noise

I’ve got an 88 Fox, 60k miles MAF converted. Semi-recently did lower intake gaskets, but in general I just let the car be how it is. I’ve noticed recently I get a dull, not necessarily thud but loud enough I can hear it at idle metallic-ish noise that I simply cannot track down. It’s got the regular tick you can hear with very close proximity, but this is not that. I’ve also got a sporadic shake at idle, but I’m fairly certain it’s an unrelated IAC issue as the car won’t die once the IAC has been unplugged. I can’t hear the noise anymore once the car goes above idle. There’s a video attached, I’m apprehensive to call it a rod knock simply because I’ve got no loss of power, am at relatively low miles, and it just doesn’t seem intense enough to be what I’ve observed in other vehicles. I’m not going to act as if I baby the car because I don’t, but I certainly don’t have a history of misshifts or redlining it. Previously it was ran a quart-ish low on oil, from what I’ve been told, but that was over a year ago. Done more than a few oil changes on it since and haven’t seen any glitter.

It’s got typical leaks and creaks but nothing (other than this) out of the ordinary. I’ve not put a gauge on for oil pressure, but the wildly inaccurate one in the cabin hasn’t given me much reason to do so outside the needle jiggling every now and again.
 
The Nods are rocking.
One at a time, pull a plug wire off of the distributor and see if the noise goes away.
If it does, you have located the cylinder with the problem.
Or, stick a brick on the throttle pedal and walk away. At some point the noise will go away and you can pick up the pieces of the problem cylinder off of your driveway.
 
The thing about it is that I first noticed this noise MONTHS ago. I hit 5500 consistently, at least 3 times a week, drive the car daily, have taken it on 5 hour roadtrips, and put nothing but 5-30 in it. I’ll try out what you said but I have a hard time believing any sort of rod failure wouldn’t have killed the cylinder completely by now.
 
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The Nods are rocking.
One at a time, pull a plug wire off of the distributor and see if the noise goes away.
If it does, you have located the cylinder with the problem.
Or, stick a brick on the throttle pedal and walk away. At some point the noise will go away and you can pick up the pieces of the problem cylinder off of your driveway.
Did what you said, pulled the wires off, and after shocking myself twice, we’ve not learned a thing other than that the noise is louder when the car is warm. Still perceivable from dead center on the lower intake manifold despite what cylinder I had off.
 
Take a look at the harmonic balancer, watch it from the side while the engine is idling, if it wiggles or wobbles it needs changing.
And run 10w-30 in it.
JMO
Oh, does it 'rattle' for a sec when you cold start it after sitting for a few days?
Will switch to 10-30 on the next oil change, I’m moving to TX anyway and it’ll be better for it. Currently live in the Appalachians so the 5-30 makes most of the year much easier. No rattle. Little Harmonic balancer movement, but not anything crazy. Could still be the culprit, but with where the noise emanates I just have a hard time with that answer. Could very well be echoing, I guess. It’s not too hard to get off, maybe I’ll give it a shot. Wanted to check my supposed 12 degree timing with a balancer that had proper visible numbers on it anyway.
 
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Reactions: General karthief
Some good info on balancers in here: