What is this noise - whining in engine bay
 

Did an oil change this evening and used Amsoil 0w30 hoping it would quieten down this cold start tap but as you can hear in the video it did not phase it. Anyway what is this whining sound from the engine bay? It is quiet a bit louder now than the last time I started the car. It gets louder with rpm's.

https://youtu.be/hGEhxAiK0S0

Since it seems to be "low" in the engine, I kind of lean towards Lifters...
Doesn't sound like rocker/spring stuff as it is pretty quiet up top

Yeah I've been dealing with that for awhile now and have about beat it to death. It is definately down low and nothing in top end, but right now the noise I was trying to figure out is that whine you hear coming from the engine bay. I was messing with the wheels earlier turning them side to side... maybe something with the power steering pump?

I was thinking maybe alternator also

mine does the same thing 01 C5. Sometimes its there sometimes its not.
that's a lifter or lifters you hear. if it was a bearing trust me, you would know. A bad bearing would sound like someone was smacking your motor with a hammer and you would hear it under the hood as well. Since you have headers it is more pronounced due to the thin wall. From the top I bet its hard to hear but once you go down its louder. I started hearing it the day I did my header swap.

This is a bad bearing

Yikes that sounds like crap, def don't have that going on. So do you think it is a damaged lifter(s) or just noisy until enough oil gets to it?

Its hard to tell, Mine usually is the opposite, when its at operating temp it starts to tick like yours, then again I have the infamous piston slap. When I drive it and then park for a few hours and start it again its like a lifter drum festival under my hood that clears up after the oil gets to the lifters. I plan on swapping out the lifters when I overhaul my heads as its way passed time (145K) as well as the pushrods. Its noisy with longtubes because the cast iron manifolds are very thick and disguise lifter ticking. The lifters will bleed off oil when its not running and then they need to be pumped again i.e hydraulic lifters. try listening to an engine with solid rollers:willy:

I'm evetually going to swap mine out also, just waiting until the money situation is right for a cam. I know long tubes amplify noise but what is odd to me is that I've listened to several c5's with long tubes that you couldnt hear any lifter noise, just the normal injector tick.

Maybe it depends on the headers, did you also go down to the ground and listen too? How many miles on your car?

Possibly.... and yeah I did listen underneath the car. You don't have to be under mine to here it, you can hear it standing 25ft away from the car. I am at 69k miles

That might be an issue then. mine you have to get close and then go under the car to hear. If yours is that loud then grab yourself a stethoscope and touch it to the valve cover going down the cylinders to identify which one is ticking the loudest. then take you valve cover off and check for play at that cylinder as far as rocker arm and pushrod. get a torque wrench and make sure they are all torqued down to spec (the rocker arms) otherwise you may have a sticking lifter that could get even worse and wipe a lobe off your cam...but that's worse case scenario.

Already been down that road. I've pulled both valve covers and listened many many times with a stethascope. Everything on top is good and you cannot issolate the noise to a specific cylinder by listened... maybe if you listened with the valve covers off you could...

Alright guys one last video I took this evening with my phone under the oil pan while I did a few revs so you can hear the sound match the revs. I am about fed up with this and ready to have my motor torn down, but don't have the cash for that right now. Towards the end of the vid after letting off the gas you can here the rattling sound trailing off the rpms.. this to me sounds like lifters but why the hell are they so loud? I know these motors are loud and I have long tubes but it sounds like my dang motor is coming apart. On a side note I cut open my oil filter this evening and checked for metal. With approx 2500 miles on that filter there were no metal chunks but under the light I could see very small specs of metal, not alot but a little here and there.. very small..Normal maybe? No chunks though....I need some trained ears to take a listen and let me know what you think. Thanks

https://youtu.be/dstUDl5E-mo

Its a lifter, The noise in the middle of your video went away for a minute then when you went back to idle it started again. Its either sticking or not pumping up

at 32 seconds in you will not hear it all, then it starts up again when you revved it at 38 seconds. If it was a bearing it would be constant.

Get the lifters replaced.

Must be just not pumping up because I have run Seafoam and Marvel Mystery Oil through it enough to where it should have freed up a sticking lifter. I just added everything up that I'm going to order to replace them and it's going to be right at $500 in just parts. Thats ls7 lifters, stock gaskets, ARP bolts, and new guide trays. :(

I hear you, I have to do the same thing, with the odometer at 144K I have to freshen up the entire top half of the motor as preventative maintenance. I do miss the good old days where you did'nt have to pull the heads to replace lifters. While you have the heads off depending on mileage you should get the springs and seals replaced too. I know it adds to the cost of the job but its better to do it all at once then have to redo it again

I spent alot of time this evening with the stethescope and I'm pretty sure I have narrowed down the sound coming from the number 1 cylinder. I am pretty confident it is one particular lifter that is chattering. I paid attention to the oil temp and the noise goes away while idling around 90. After it disappears you can still hear the chatter when you let off throttle. The chattering trails off after you get off the gas. I am going to pull the driver side valve cover tomorrow and check the rocker bolt torque and also the pushrods on cylinder 1.

Yesterday I replaced my passenger header gasket, and the noise was loud as ever underneath. This morning I went to the gym and when I started it up the noise was gone. On my way home from the gym I started it up and iot was ticking pretty loud for about 15 seconds then went away. I got home and listened again and nothing. I'm not worried, it will be back again lol. Im buying new heads along with new lifters pushrods, rockers with new trunions, and just refresh the entire top of the motor.

Thats odd to be intermittent like that. So do you think your tick is exhaust related? I would like to replace the entire too end but I can't afford that at the moment.

I cant afford it either, but while its apart I might out as well do it the first time.