Two Issues....
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Launching!
Joined: Mar 2009
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From: Chesterfield, VA
Two Issues.... Sorry for the dumb questions in advance. I'm a gearhead from the 70s and feel much more adept under the hood of my 'Cuda than I do 4th Gen TA's....
2001 WS6, H/C/I/E. Whistling, almost Procharger sounding (I wish) under the hood. First reaction was vacuum leak but I can't tell where it is coming from no matter how hard I try to pinpoint it. Any ideas?
Also- a lot of ticking sounds at idle which makes me think valve train but another LS1 guy told me his has always done it. I've only had the car for a year- it has 50K on the clock. After market everything under the valve covers. Is it routine to have to adjust the valves or are LS1s notorious for noisy engines?
2001 WS6, H/C/I/E. Whistling, almost Procharger sounding (I wish) under the hood. First reaction was vacuum leak but I can't tell where it is coming from no matter how hard I try to pinpoint it. Any ideas?
Also- a lot of ticking sounds at idle which makes me think valve train but another LS1 guy told me his has always done it. I've only had the car for a year- it has 50K on the clock. After market everything under the valve covers. Is it routine to have to adjust the valves or are LS1s notorious for noisy engines?
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
What sort of aftermarket valvetrain/cam do you have? Yes, even stock LS1s are a bit noisey, and with a cam/supporting hardware they tend to get even louder.
Valve adjustments should only be for solid lifter cams. If you're still using a hydro cam there shouldn't be any adjustment needed after the initial setup.
Valve adjustments should only be for solid lifter cams. If you're still using a hydro cam there shouldn't be any adjustment needed after the initial setup.
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
Thread Starter
Launching!
Joined: Mar 2009
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From: Chesterfield, VA
Yeah, it's definitely a sewing machine sound. Just want to be sure I'm not allowing something to get worse if I can stop it in its tracks early. Here's the description from the previous owner on the car's aftermarket setup:
-FLP Long Tube Headers with HiFlo Cats. 3" exhaust all the way.
-AFR 228/228 Cam, 568 lift
-Comp valve springs, titanium retainers, chromemolly pushrods
-LS6 Composite intake
-Richmond 4:10 gears, TA Performance Aluminum rear axle girdle with stud kit
-Direct Flow intake with K&N
-B&M Short Throw shifter
-Stage 3 Ceramic/carbon clutch
-BMR Struttowerbrace,subframe connectors, adjustable panhard bar, upper and lower control arms
-Baer eradispeed drilled and slotted rotors
Still wondering about the whistle also. Am I on the right track with a vacuum leak?
RPM WS6- yeah those were the days when you could sit inside the fender wells with a beer and work on your car.
-FLP Long Tube Headers with HiFlo Cats. 3" exhaust all the way.
-AFR 228/228 Cam, 568 lift
-Comp valve springs, titanium retainers, chromemolly pushrods
-LS6 Composite intake
-Richmond 4:10 gears, TA Performance Aluminum rear axle girdle with stud kit
-Direct Flow intake with K&N
-B&M Short Throw shifter
-Stage 3 Ceramic/carbon clutch
-BMR Struttowerbrace,subframe connectors, adjustable panhard bar, upper and lower control arms
-Baer eradispeed drilled and slotted rotors
Still wondering about the whistle also. Am I on the right track with a vacuum leak?
RPM WS6- yeah those were the days when you could sit inside the fender wells with a beer and work on your car.
Joined: Nov 2001
Posts: 34,628
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From: Schiller Park, ILL Member: #317
Your cam is medium-ish sized as far as LS1 cams go. But I would certainly expect a bit of sewing machine sound, especially with the headers. However, here are a couple things to think about with regards to any ticking:
- Do you still have the factory AIR system hooked up? You mentioned having cats, so it's reasonable to assume that someone may have left the AIR intact. If so, the check valves are notorious for fluttering/ticking when headers are added. You can either delete the system completely, or install restrictor plates to stop the noise. However, once the valves are fried, there is no fixing them - you'd need to start with new ones at the same time as adding the restrictor plate.
- You mentioned Comp springs. Can you find out which ones? Several batches of the common 26918 springs have had breakage issues over the years. That would be a common spring choice for a cam the size of yours. Might not hurt to pull the valve covers and inspect them, if you really think that the noise is loud enough to be a concern.
As for the whistle.... any chance it could be a pulley squeek? Or are you sure it's air rushing past something (like a vac leak?). Idler and tensioner pulleys are known to squeek on these cars as they age.
- Do you still have the factory AIR system hooked up? You mentioned having cats, so it's reasonable to assume that someone may have left the AIR intact. If so, the check valves are notorious for fluttering/ticking when headers are added. You can either delete the system completely, or install restrictor plates to stop the noise. However, once the valves are fried, there is no fixing them - you'd need to start with new ones at the same time as adding the restrictor plate.
- You mentioned Comp springs. Can you find out which ones? Several batches of the common 26918 springs have had breakage issues over the years. That would be a common spring choice for a cam the size of yours. Might not hurt to pull the valve covers and inspect them, if you really think that the noise is loud enough to be a concern.
As for the whistle.... any chance it could be a pulley squeek? Or are you sure it's air rushing past something (like a vac leak?). Idler and tensioner pulleys are known to squeek on these cars as they age.
Last edited by RPM WS6; Oct 22, 2010 at 03:27 PM.
Thread Starter
Launching!
Joined: Mar 2009
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From: Chesterfield, VA
The AIR system was intact when I bought the car but I deleted it myself. Where exactly are the check valves you are talking about? I pulled the big honkin' AIR unit under the driver's front fender but nothing else.
Also- yes, I need to pull the valve covers to see what's under there. Been putting it off but just need to suck it up when I have the free time (my free time for wrenching is limited these days). The interesting thing about the sewing machine sound is that it does not do it all of the time. That said, I haven't found a pattern to when it does it. I want to say it does it more before it is warmed up but I think it randomly comes and goes which says improper oil distribution to me. Hmmmm....
Also- yes, I need to pull the valve covers to see what's under there. Been putting it off but just need to suck it up when I have the free time (my free time for wrenching is limited these days). The interesting thing about the sewing machine sound is that it does not do it all of the time. That said, I haven't found a pattern to when it does it. I want to say it does it more before it is warmed up but I think it randomly comes and goes which says improper oil distribution to me. Hmmmm....
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From: Schiller Park, ILL Member: #317
The AIR system was intact when I bought the car but I deleted it myself. Where exactly are the check valves you are talking about? I pulled the big honkin' AIR unit under the driver's front fender but nothing else.
Also- yes, I need to pull the valve covers to see what's under there. Been putting it off but just need to suck it up when I have the free time (my free time for wrenching is limited these days). The interesting thing about the sewing machine sound is that it does not do it all of the time. That said, I haven't found a pattern to when it does it. I want to say it does it more before it is warmed up but I think it randomly comes and goes which says improper oil distribution to me. Hmmmm....
Also- yes, I need to pull the valve covers to see what's under there. Been putting it off but just need to suck it up when I have the free time (my free time for wrenching is limited these days). The interesting thing about the sewing machine sound is that it does not do it all of the time. That said, I haven't found a pattern to when it does it. I want to say it does it more before it is warmed up but I think it randomly comes and goes which says improper oil distribution to me. Hmmmm....
Might also be a lifter tick or common piston slap if it comes and goes like that....
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Launching!
Joined: Mar 2009
Posts: 203
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From: Chesterfield, VA
The AIR check valves are the small, black, round-ish ball/lump looking things that connect between the hard AIR pipe comming off the header/manifold, and the rubber line going to the AIR pump. They are threaded on the hard-pipe end and zip-tied on the rubber line end (hope that makes sense). If you capped off the AIR provisious on the headers when you removed the AIR system, then these valves are already removed/out-of-service.
Might also be a lifter tick or common piston slap if it comes and goes like that....
Might also be a lifter tick or common piston slap if it comes and goes like that....
BTW- I got this car in Chicago. How far are you from there?
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
I'm about 1/2 mile north of Chicago. The south end of my town boarders Chicago.
Thread Starter
Launching!
Joined: Mar 2009
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From: Chesterfield, VA
Yeah, if you pulled the pump already then you might as well just remove the rest. You can just cap off the AIR provision at the header tube (a simple fabbed up piece of metal with a gasket will do) and delete all the rest of the junk.
I'm about 1/2 mile north of Chicago. The south end of my town boarders Chicago.
I'm about 1/2 mile north of Chicago. The south end of my town boarders Chicago.
Joined: Nov 2001
Posts: 34,628
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From: Schiller Park, ILL Member: #317
I don't recognize the name, but it's possibile I may have seen the car at some point. I hit a few local cruise locations every weekend, and there's always some LS1 cars on hand. But, Chicago is a huge city, so it's probably more likely that I've never seen this one. Do you know if the car came from the city proper or a local suburb?
Yeah, if you pulled the pump already then you might as well just remove the rest. You can just cap off the AIR provision at the header tube (a simple fabbed up piece of metal with a gasket will do) and delete all the rest of the junk.
I'm about 1/2 mile north of Chicago. The south end of my town boarders Chicago.
I'm about 1/2 mile north of Chicago. The south end of my town boarders Chicago.
Thread Starter
Launching!
Joined: Mar 2009
Posts: 203
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From: Chesterfield, VA
I don't recognize the name, but it's possibile I may have seen the car at some point. I hit a few local cruise locations every weekend, and there's always some LS1 cars on hand. But, Chicago is a huge city, so it's probably more likely that I've never seen this one. Do you know if the car came from the city proper or a local suburb?
Thread Starter
Launching!
Joined: Mar 2009
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From: Chesterfield, VA
Thought I would post a vid of the engine sounds- not sure if this will help, but...
http://smg.photobucket.com/albums/v4...t=M4H00179.mp4
http://smg.photobucket.com/albums/v4...t=M4H00179.mp4
Joined: Nov 2003
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From: Wichita KS / Rancho San Diego
There is a vacuum orifice on the driver's side rear for the AIR system that must be plugged if you remove the system. If you have the hoses still hooked up and the pump removed, you have a vacuum leak.
Thread Starter
Launching!
Joined: Mar 2009
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From: Chesterfield, VA
Everything is plugged up- still have the sound. Starting to wonder if it is not a vacuum leak but a high pitched squeel from the undercrank pulley. Listen to the video that I posted above- you'll hear the pulley squeeking after the engine shuts down. The sound I hear gets louder under increased load (when the vacuum goes down not up).
What the heck was that at the very end of video? What was still spinning after engine turned off. Why is the pulley still turning after engine is stopped? What ever is still spinning and making that squeak must be your culprite.
Thread Starter
Launching!
Joined: Mar 2009
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From: Chesterfield, VA
OK you're freaking me out dude. Guess I'll be taking a much closer look at the squeaky culprit on shutdown.