Ok that is Different. It built up pressure OR vacuum then released. Air Pump? Exhaust air tubes. It is up front. The Knocking is hard to gauge. It could be exhaust. Use a scope. or listen to the Oil pan. check your vacuum. With a gauge. your idle was slightly high. Does it drop down 700 range.

 

Thanks.

Sorry, what built up pressure/vacuum? Are you saying the sound could be from pressure in the AIR injection system?

What part of the exhaust would cause knocking like that? (Just so I know where to focus my search)

I'll check the vacuum if I can find a gauge to borrow from O'Reilly or Autozone or the like. Otherwise would the sensor reading work?

Honestly, I'm not 100% sure what's normal for the idle. I went through the base idle screw adjustment procedure a few times since I got the new motor but I haven't really been paying attention since then. If I remember correctly the idle is where it should be.

 

Noise in the 2nd vid sounds like a bad pulley/bearing to me. A dry bearing will squeal similar to your noise.

Remove the belt, check all pulleys for wobble + rotate them. If you feel any roughness or have any play replace the part. Tensioner & idler failure is common.

Check balancer pulley bolts & hub bolt when servicing the pulleys.

 

I checked them all and they all seemed fine. The alternator had a bit of a wobble, but not bad (it's new), the smog pump had not so much of a rough spot as a spot with more friction (it's also new), and the AC compressor pulley is a bit misaligned. The only one of those that has arisen recently is the AC misalignment, which is due to some modification to the bracket I had to do.

What exactly should I be checking the balancer bolts and hub bolt for?

 

You had everything apart make sure all of the bolts are tight.

Run the engine for a minute with the belt removed. If the noise is gone you have located the problem area. If the noise persists you have eliminated the belt/pulleys as the problem area.

Engine running: Use a long screw driver in your ear & touch each component as it rotates. Any bearing noise will be apparent.

Stick a length of vacuum or fuel line in your ear & listen around the engine to locate the noise source. You need one of these:
http://www.harborfreight.com/mechani...ope-69913.html
Remove the metal pointer to use as a listening device for non metallic noise.
Good luck

 

Thanks for the help.

Just to be clear, you are talking about the clattering startup noise, not the squealing noise while accelerating, right?

I ran it with the belt off and the clattering noise is definitely still there. I didn't have much luck with the screwdriver method, but when I laid next to my car it sounded like the noise was coming from inside the oil pan.

Next I need to drive it up on my ramps and see if I can isolate the noise from underneath. I'll inspect the crank pulley bolts too to be sure. When I get to this will be dictated by my progress hunting down the original squealing noise I was looking for.

 

I addressed both issues. Belt/pulleys for the squealing noise, loose crank pulley for the rattle.

Rattle @ start up & idle is inconsistent = the rotating assembly is ok.

The dual mass flywheel is suspect it will rattle @ idle if the engine is not running perfectly smooth. Mine began to rattle @ idle when the stock multi tech injectors started to fail = a half hearted miss fire caused flywheel rattle @ idle.

Depending on the replacement camshaft profile it may be the cause the flywheel rattle.
Listen @ the bell housing with the screw driver in your ear if the noise is loudest there
you have a dual mass rattle.

 

Oh, I get it. I'll drive it just down the street with the belt off to see if it squeals still to eliminate that.

I drove it up on the ramps after a test drive today, so I can listen for the rattle's location when I start it next. It makes sense that it's the flywheel since I failed to have my flywheel rebalanced for my new engine.

Thanks for your help!