LB7: Chattering noise? sound clip included

[beanpole209]

I have a 03 LB7. For about 3 weeks it has had an intermittent chatter noise coming from the lower, passenger side of the engine bay. Alteast that is where the sound is strongest. I have replaced both idler's, and tensioner pulley's before, they do not appear to be the culprit.

I drove home for Easter yesterday, about 160 miles. I couldn't hear the noise for the most part, only when I was going less than 35-40 MPH, and could barely hear it without the front passenger window down.

Today I had to drive it about 15 miles and it seemed much louder. Weirdly, it is still intermittent, and in park I had to rev it a little to make it do it. Also, the chatter goes faster, and gets louder with engine RPM.

My phone it messed up, and I could only get a 3gp sound file recorded. It plays in quicktime. It starts in front of the passenger side of engine bay, then I moved towards & left of the ALT, then passenger side wheel well. Thanks for any input. http://www.filedropper.com/truckrattle

 

[blk smoke lb7]

I have a 03 LB7. For about 3 weeks it has had an intermittent chatter noise coming from the lower, passenger side of the engine bay. Alteast that is where the sound is strongest. I have replaced both idler's, and tensioner pulley's before, they do not appear to be the culprit.

I drove home for Easter yesterday, about 160 miles. I couldn't hear the noise for the most part, only when I was going less than 35-40 MPH, and could barely hear it without the front passenger window down.

Today I had to drive it about 15 miles and it seemed much louder. Weirdly, it is still intermittent, and in park I had to rev it a little to make it do it. Also, the chatter goes faster, and gets louder with engine RPM.

My phone it messed up, and I could only get a 3gp sound file recorded. It plays in quicktime. It starts in front of the passenger side of engine bay, then I moved towards & left of the ALT, then passenger side wheel well. Thanks for any input. http://www.filedropper.com/truckrattle

That web site wants to add a bunch of stuff on my computor can you post a youtube video and link it on here?

 

[beanpole209]

Ok, I finally have a video up! I'm hoping Its a pully, but without the belt off none of the pulley's appear to be bad. Thanks you any help!

[YOUTUBE]qpZOtKpzRlI&feature=youtu.be[/YOUTUBE]

 

[beanpole209]

For some reason the usual youtube tag on here now isn't working, so here is the link.

http://youtu.be/qpZOtKpzRlI

Edit: started working LOL

 

[blk smoke lb7]

Id take the whole intake off and make sure you dont have something like a screwdriver in there lol sorry i had to do that for Joe.I would pull the intake and check it out.The harmonic ballencer isnt wobbeling is it?Valve train? Turbo wheel hitting the housing?

 

[beanpole209]

Id take the whole intake off and make sure you dont have something like a screwdriver in there lol sorry i had to do that for Joe.I would pull the intake and check it out.The harmonic ballencer isnt wobbeling is it?Valve train? Turbo wheel hitting the housing?

I really appreciate the input, and lol at the screwdriver reference.

Crawled around looking for answers, and so far nothing out of the ordinary. The balancer, and all of the pulley's on initial inspection all seem solid. OP is normal, temp, and all stats are normal. It has plenty of power, and drives normally except for sound. I doubt its the turbo because the location of sound, but It will get checked.

Loosely thinking it is one of four things. Vacuum pump (LB7-EGR edition lol), valve train, water pump, exhaust leak of sorts. Sounds like surgery is becoming likely!

 

[jkholder09]

take belt off and run it does noise go away??

 

[TheBac]

Vacuum pump could sound like that. Do you have an aftermarket exhaust? Check the downpipe/frontpipe connection.

 

[fullpullalex]

I have a 03 LB7. For about 3 weeks it has had an intermittent chatter noise coming from the lower, passenger side of the engine bay. Alteast that is where the sound is strongest. I have replaced both idler's, and tensioner pulley's before, they do not appear to be the culprit.

I drove home for Easter yesterday, about 160 miles. I couldn't hear the noise for the most part, only when I was going less than 35-40 MPH, and could barely hear it without the front passenger window down.

Today I had to drive it about 15 miles and it seemed much louder. Weirdly, it is still intermittent, and in park I had to rev it a little to make it do it. Also, the chatter goes faster, and gets louder with engine RPM.

My phone it messed up, and I could only get a 3gp sound file recorded. It plays in quicktime. It starts in front of the passenger side of engine bay, then I moved towards & left of the ALT, then passenger side wheel well. Thanks for any input. http://www.filedropper.com/truckrattle

Check to see if the bracket on the downpipe that connects it to the up pipes at the manifold is broken. Mine is and honestly dont feel like bothering with it. The little chatter is only noticeable over large bumps.

 

[beanpole209]

take belt off and run it does noise go away??

Ill do that tomorrow for sure!

Vacuum pump could sound like that. Do you have an aftermarket exhaust? Check the downpipe/frontpipe connection.

I have a straight pipe, I will check all of the exhaust in and around. If its the vacuum pump, does it run anything other than the egr, like the brakes? I forgot. FYI, my egr is blocked, and I just never got around to removing the VP.

Check to see if the bracket on the downpipe that connects it to the up pipes at the manifold is broken. Mine is and honestly dont feel like bothering with it. The little chatter is only noticeable over large bumps.

That would be awesome, well I hate anything being broke but it would be better than a valve or something.

Thanks for the input guys! With my medical issues, I really have research stuff before I exert all my energy into fixing something.

 

[beanpole209]

Well, no sound with the belt removed!!!!!! so happy!

None of the pulleys are bad, so i guess its that VP making the noise! Right now I can't see how to remove it with everything in the way. Does anyone by chance have a Mitchell account, or a writup? I assume it's probably the same on 1st gen LLY's but, idk.

I appreciate all the help, thank yall for taking the time!

Sent from my DROIDX using Tapatalk 2

 

[trevrosborough]

sounds like the fan hitting the fan shroud i would be checking that before i go pulling everything apart

 

[07keo02]

For the split second I could see it I thought the belt tensioner was bouncing around. Edit, watched it some more and could have been the camera angle and shake for the second it came into view.

 

[jkholder09]

now mount a bike to the passenger fender and hook a belt from rear tire to each accessory. pedal really hard until you find the noise:roflmao:

 

[beanpole209]

sounds like the fan hitting the fan shroud i would be checking that before i go pulling everything apart

205000 miles on the stock motor mounts, I could definitely see that. The fan doesn't hit when spun by hand, and the sound doesn't appear to emanate from that area, but I will keep it mind for sure!

For the split second I could see it I thought the belt tensioner was bouncing around. Edit, watched it some more and could have been the camera angle and shake for the second it came into view.

That was my initial thought because I replaced it about a month ago. Though, that shake is my old crappy DX phone, and my awesome camera skills! Also, I messed around with it and its still tight as the day I put on.

Edit, I meant the pulley.

now mount a bike to the passenger fender and hook a belt from rear tire to each accessory. pedal really hard until you find the noise:roflmao:

:thumb:

 

[beanpole209]

So, I just wanted fill in the conclusion to this problem. It was the vacuum pump. Got it fixed a while back, and its been going good since!

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