2001 LS 3.9L V8. So my car makes this horrible noise which I believe to possibly be the IAC (idle air control) valve. I have removed and cleaned it and the noise has stayed the same if not possibly worse. I have also read on here that it may be impending transmission failure. Tranny has 30k after rebuild with new TC and upgraded to Merc V. So I really hope that is not the issue. I also removed the belt and found my water pump is a little squeaky when rotated by hand but all other pulleys and idlers are solid. The belt had a bunch of little rocks imbedded in it but I cleaned those out. Ran the car for a few seconds with the belt off and nothing stood out.
This noise is very elusive and actually hard to record. It makes the noise almost every afternoon on my drive home RIGHT after I exit the freeway as I am coming to a stop and def after I have stopped and first hit the gas to go again. By the time I get to my house the noise is usually gone and hard to reproduce. If I get in the car after it has sat for an hour it will sometimes make the noise right away. It doesn't stay consistent with RPM and sounds like it on its own frequency. Sounds very much like air in a hydraulic system. Both power steering and fan pump have been drained and filled with merc V and even threw in friction modifier for the power steering. Have applied a vacuum on both of these for 30 min while running and have also replaced the power steering pump sensor and the fan pump high / low speed sensor. The noise is def on the drivers side and from the front corner. Haven't been able to def say it is in the intake because it goes away by the time I can get it open (trying to verify if IAC). I have heard about the new IAC not working nightmare and don't want to throw away $100 on a bad brand new IAC and that not be the problem. My A/C is Luke warm and most def low on refrigerant so it could also be the compressor but it makes the noise if A/C is on or off and the clutch doesn't feel crunchy when rotated with the belt removed. No yellow liquid under the pump either.
What I would really like to do is find anyone who has heard this noise and found the problem maybe help shed some light on my predicament. Here are a few vid clips of the noise...under the hood is most noticeable around the 11 sec mark. The interior is not as loud but more of the change in pitch is caught on camera. (Feels like I am chasing nessy!)
Thank you in advance for any help on this mystery.
[youtube]WW-EeeIlnyU[/youtube]
[youtube]UANr81MUXZw[/youtube]
[youtube]7CBGNJBXOww[/youtube]
http://www.youtube.com/watch?v=7CBGNJBXOww&feature=share&list=UU-29FE_6JK76vyFt-SiqRSg
http://www.youtube.com/watch?v=WW-EeeIlnyU&feature=share&list=UU-29FE_6JK76vyFt-SiqRSg
http://www.youtube.com/watch?v=UANr81MUXZw&feature=share&list=UU-29FE_6JK76vyFt-SiqRSg
This noise is very elusive and actually hard to record. It makes the noise almost every afternoon on my drive home RIGHT after I exit the freeway as I am coming to a stop and def after I have stopped and first hit the gas to go again. By the time I get to my house the noise is usually gone and hard to reproduce. If I get in the car after it has sat for an hour it will sometimes make the noise right away. It doesn't stay consistent with RPM and sounds like it on its own frequency. Sounds very much like air in a hydraulic system. Both power steering and fan pump have been drained and filled with merc V and even threw in friction modifier for the power steering. Have applied a vacuum on both of these for 30 min while running and have also replaced the power steering pump sensor and the fan pump high / low speed sensor. The noise is def on the drivers side and from the front corner. Haven't been able to def say it is in the intake because it goes away by the time I can get it open (trying to verify if IAC). I have heard about the new IAC not working nightmare and don't want to throw away $100 on a bad brand new IAC and that not be the problem. My A/C is Luke warm and most def low on refrigerant so it could also be the compressor but it makes the noise if A/C is on or off and the clutch doesn't feel crunchy when rotated with the belt removed. No yellow liquid under the pump either.
What I would really like to do is find anyone who has heard this noise and found the problem maybe help shed some light on my predicament. Here are a few vid clips of the noise...under the hood is most noticeable around the 11 sec mark. The interior is not as loud but more of the change in pitch is caught on camera. (Feels like I am chasing nessy!)
Thank you in advance for any help on this mystery.
[youtube]WW-EeeIlnyU[/youtube]
[youtube]UANr81MUXZw[/youtube]
[youtube]7CBGNJBXOww[/youtube]
http://www.youtube.com/watch?v=7CBGNJBXOww&feature=share&list=UU-29FE_6JK76vyFt-SiqRSg
http://www.youtube.com/watch?v=WW-EeeIlnyU&feature=share&list=UU-29FE_6JK76vyFt-SiqRSg
http://www.youtube.com/watch?v=UANr81MUXZw&feature=share&list=UU-29FE_6JK76vyFt-SiqRSg
