2005 Tahoe 5.3l engine whine

[wreedps]

Hey guys I have a engine whine noise on my 2005 Tahoe with 122k that sounds like it is coming from the alternator or PS pump. The whine increases with engine RPM and is pretty much always there.

The truck is bone stock 2wd with 122k miles on it. Been great, no major issues. Before I just start replacing things, what are common whines in these 5.3l?

 

[jhacker5150]

There are a number of different possibilities ... if it's consistent at nearly any RPM there's a good chance it could be either of what you mentioned (alternator and/or PS pump).

I'd slip your belt off and run the engine momentarily to see if the noise goes away - or changes pitch perhaps.

One tool I'd recommend for helping to narrow down random noises is the Lisle Mechanic's Stethoscope http://www.amazon.com/Lisle-52500-Mechanics-Stethoscope/dp/B0002SQYSM/ref=sr_1_2?s=automotive&ie=UTF8&qid=1392097265&sr=1-2&keywords=lisle+stethoscope

 

[wreedps]

Yeah I have a new belt anyway . I am going to check that this weekend. Anyone else input is welcome.

 

[Rivieraracing]

Not sure if you have a harbor freight by you or not but get a hold of one of those automotive stethoscopes that you can hold up to each component to see if they are causing the noise! I bought mine a few years ago from HF for a few bucks and it's helped me diagnose noise problems a few times already, works pretty good!

 

[wreedps]

OK So i flushed the PS fluid and replaced the belt and idler pulley. Noise remains. I am going to get a mechanics stephascope. Makes the whine with the AC on or off, also in neutral.

Any other ideas of what it could be?

Steering is alot smoother now though!

 

[livingez_123]

A long handle screwdriver works as a stethoscope too! does the sound change when you turn your steering wheel? if it does you found your sound. mine has a slight whine when it's real cold out.

 

[Rivieraracing]

A long handle screwdriver works as a stethoscope too! does the sound change when you turn your steering wheel? if it does you found your sound. mine has a slight whine when it's real cold out.

I forget about the screw driver trick, just watch yourself when being that close to the serp belt with your head on the screw driver!

 

[wreedps]

Still havent fixed this, anyone got any ideas!!???

 

[Rivieraracing]

What did you try since your last response?

 

[ccapehartusarmyINF.(ret)]

best guess is bad alternator diode
the alternator diodes basically keep ripple voltage to a minimum and when one fails the ripple voltagle increases significantly along with a noticeable whine