need help in Diagnosing unusual engine noise

[need2boostpsi]

Well i have been running my car for some time with a broken downpipe, until today. I got my new downpipe installed and the car is much quieter. So much quieter that i can hear a loud rattle/ almost high rpm knocking, but not rod knock. It's coming from around the engine can't seem to pin point it but its sounds louder on top of the car then under the motor. sounds like something off balance or a loud rattle. Only does it when you free rev it and the RPM's go up and down. doesn't seem to make the noise at idle, and while driving and partial giving the car gas, it seems like it starts making the sound around 1500 RPM's. Under full throttle sound goes completely away, and lastly it seems to do it worse when the engine warms up. well I freaked out and parked the car in my workshop (not gonna drive it tell i get it fixed. So today i decided to do a little bit of searching for the sound through the process of elimination. I pulled my water pump belt/alt belt off and AC belt off, started the car and the sound was still there, my car went into idle surge because the FIAV valve was now not seeing any coolant. so when it was revving itself up and down i could hear the noise still, checked the harmonic balancer for any wobble and noise and didn't see or hear any. Next I drained the oil into a clear container and ran a magnet around in it. didn't pull up any metal shavings. I decided to pull the oil pan anyways and check it for a gray mud at the bottom which would be shavings, none there and my motor was rebuilt 1000 miles ago and the crank, rods, and rod bearings are all new. while the oil pan was down i checked the rod bearings for any up and down play, none. but there was side to side play which i think is, normal? put it all back together and started it up, noise still there.Please, i need help in diagnosing the strange sound. BTW my car runs and idles fine, no power loss. Thanks for any help!

 

[majik2k5]

Could be your lifters.

 

[JessesTalon]

Although lifter tick is common in dsm's from what he wrote I don't think the lifters are whats ticking... usually lifter tick is when you start up and when it warms up it for the most part gets real quiet or goes away.

are you using regular or synthetic oil?

 

[need2boostpsi]

Although lifter tick is common in dsm's from what he wrote I don't think the lifters are whats ticking... usually lifter tick is when you start up and when it warms up it for the most part gets real quiet or goes away.

are you using regular or synthetic oil?

Im using mobil one 10w-30. as far as lifter tick, it's more of a knock/rattle. i'll post a clip here in a minute.

 

[need2boostpsi]

ok here it is http://videos.streetfire.net/player.aspx?fileid=462AE84A-89DA-4707-B388-191B78F74D1F

 

[need2boostpsi]

sound still there, shop told me it was my balance shafts, told me that my engine was probably shot. The car runs so smooth and was rebuilt 2,000 miles ago??? I need some input please. I'm in the process of eliminating my Balance shafts and I don't see any shavings and the bearings all look new.

 

[Vandal]

Check and make sure your spark plugs aren't loose

For a while there I thought I had a lifter issue. Then one day I put my hand on the top of the plug wire and felt the plug vibrating..tightened it and walaa! noise is gone.

 

[JDP AWD 1g]

ok im having a few weird problems. ive heard 2 other dsm's with the same noise i have both ran fine till they were sold and parted out.

i have a loud whine or hum comin from the timing side of the motor. this started after i blew my stock 14b turbo. and now along with the humming it sounds like there is marbles rolling around inside my valve cover....any ideas?

 

[need2boostpsi]

well i replaced the balance shafts with the kit, started it up and it still makes the noise. sounds like its coming from my head.

 

[need2boostpsi]

just to update for everyone else, the noise turned out to be spun bearings on all 4 rods the mechanic that rebuilt the motor should have probably stuck to carbed v-8's

 

[icer412]

if you spun the bearings, did you notice any metal shavings in the oil or oil pan ?

 

[ontario AWD]

I would say the "mechanic" should find a new profession,or go to the nearest hardware store and buy a piece of rope that fits snuggly around his neck

 

[dsmboy51]

hmmm, that is what my engine sounded like when the hydraulic tensioner went to crap.

 

[Colt4G63 also]

Did your "mechanic" put undersize bearings on standard size rod journals, or just leave a gear out of the oil pump? I've never heard of all four rod bearings spinning. I would be pissed.