SSBenj

I recently finished up my lsx swap and everything was going good until I heard this nasty screeching noise. At first I thought it was my power steering pump because the high pressure hose was leaking. I replaced it and the sound was still there. I ran the car without the belt and the sound did not go away. I thought it was the ati pulley so I put the stock pulley and the sound went away. The next day I let the car idle for about 20-30 minutes(oil pressure at cold start is 60psi then after a while it goes down to 35-40psi I'm running the Melling 10296) before I went for a 3 mile ride around the neighborhood. As I was pulling up to my driveway the screeching noise came back. There is no metal shavings in the oil. I took out the timing cover see if anything was rubbing but nothing. Right now I'm in the process of removing the cam to check the bearings. I have been searching on all the forums and YouTube to find a similar sound or problem but I have had no luck. If anyone knows what this could be or has had similar issues let me know how it was fixed. Here is a YouTube link of the sound on the stock pulley with the belt on the car turns off bc I has not been tuned yet. http://www.youtube.com/watch?v=KnEhXMFjM4U&sns=em

Thanks,

Ben

WarmWeatherBird

Hmm. If you've ruled it out, then it's probably not helpful - but the only screeching sound like that I've ever had was related to the power steering pump being low on fluid. I noticed that I started getting this horrible grinding screech sound when I made a hard right turn into the grocery store parking lot off the main road. It seemed to be the only place it would do it - only identifying characteristic of that turn versus another was that they had a somewhat steep grade/dip into the drive. Everyone said - oh you've got a bearing screaming - but when testing it in the cul-de-sac, it would screech without actually moving the car - at a complete stop - just from turning the wheel really hard. Turned out my ps fluid had gotten pretty low in the reservoir and it was making the angry sound as it tried to push the fluid from one side to the other when I made an extreme turn. But it was a kind of grinding screech sound. Yours sounds more high pitched.

I've been chasing squeaks through my 2002 the last month - have eliminated all but one. My dad had a pulley lock and rip off his SUV on the highway - threw it through the radiator like a baseball so I have much respect for the squeaky pulley now. I replaced both idler pulleys and a tensioner pulley as well as one tensioner assembly. The water pump is only 30k miles old. Alternator is a big 253 amp dog that's less than 2 years old. Also swapped out my belts for more quiet gatorback belts. I actually had 3 month old dayco belts on there that were squeaking. I didn't think it was - but one of the guys showed me a neat trick to identify a squeaking belt: Get a crayon. Draw a little on the outside of the belt while it's turning and see if it quiets down. If not - try it on the AC belt. If that doesn't do it - draw a little on the inside of each belt. Sure enough - I had a little squeak coming from my 3 month old belt. Go figure. So now I'm getting ready to investigate the balancer and see if that could be the source of my last little car canary.

Let us know what you figure out!

SSBenj

Thanks for the input man. Mine does the noise with the belt off too. I checked my bearings everything looks good my cam looks good, and lifters are good too. I noticed that the oil pump summit sent me was a used pump because the bolt to change the spring was stripped. I Have a new one ready to install see if this fixes that issue.

WarmWeatherBird

Ooh! Hadn't thought about the oil pump being the cause. I might do some more searching on mine this weekending trying to run it down. Please do post whether that pump swap resolves it!

Crimsonnaire

iTrader: (1)

I've had the screeching problem once after I had my power steering pump changed. I chased after a couple pulleys until it was revealed to me that it's actually coming from the belt being run across misaligned pulleys. Afterward, I had the PS pulley reinstalled since that was the part changed and the noise went away after making sure that the pulley is all the way in the mounting shaft. However, one distinction I must point out is that the screeching I had is really high pitched and only got louder with higher RPM's, whereas yours has a metallic sound and only gets lower with rising RPM. If it is coming from two metal surfaces rubbing, it would correlate to the sound becoming faint with a higher RPM due to the rise in oil pressure and flow.

In a situation where you really can't pinpoint a noise, it may be helpful to use a stethoscope. Once you identify the general area of the source, it shouldn't take much for you to deduce the faulty part.