Is this noise something more than normal LS1 noise. (sound clip)
04-12-2007, 11:57 PM
#1
Is this noise something more than normal LS1 noise. (sound clip) I just started getting this valve chatter noise. It didn't make this noise before I installed a PTB, replaced a bad check valve, and changed the oil twice. First mobile 1 0W-40, then 5w-40. Oil pressure is good and it runs good but it also makes this same type of chatter at low rpm's when it first shifts into 2nd and 3rd gear under light throttle. It's a lot worse in 2nd than 3rd.
In the video you can hear it best toward the end when the rpm's are coming down it sounds like valve chatter. I'm no expert but to me it also sounds like I might also have a vacuum leak when I first press the throttle cam the last few times but I can't seem to find it if there is one.
I'm still new to these motors so I'm not exactly sure what normal is but I don't think this noise is normal. I kind of think it has to be something I did. Maybe the check valve is the wrong one or I have a vacuum leak somewhere.
http://s132.photobucket.com/albums/q...ent=072306.flv
In the video you can hear it best toward the end when the rpm's are coming down it sounds like valve chatter. I'm no expert but to me it also sounds like I might also have a vacuum leak when I first press the throttle cam the last few times but I can't seem to find it if there is one.
I'm still new to these motors so I'm not exactly sure what normal is but I don't think this noise is normal. I kind of think it has to be something I did. Maybe the check valve is the wrong one or I have a vacuum leak somewhere.
http://s132.photobucket.com/albums/q...ent=072306.flv
04-13-2007, 03:25 AM
#2
TECH Addict
A bad check valve as in AIR check valve? Logically, a valve noise would not start because of that, why did you change the oil twice?
It would seem that your check valve gasket may be leaking. Other than that it is very difficult to hear anything on your video.
It would seem that your check valve gasket may be leaking. Other than that it is very difficult to hear anything on your video.
04-13-2007, 08:10 AM
#3
Yeah, it was a bad Air check valve that I replaced on the driver's side and the noise is definitely coming from the passenger side of the motor.
I changed the oil twice because I was using 5w-40 and when I changed it I tried 0w-40 because that tested better for our engines according to BTOG. Once it started making that noise I wanted to see if that might be what was causing it so I changed back to the 5w-40. I was also concerned that on the bottle of Mobile1 0w-40 it said "European car formula" on it. It never used to say that so I thought maybe they changed something in it that the LS1 doesn't like.
I changed the oil twice because I was using 5w-40 and when I changed it I tried 0w-40 because that tested better for our engines according to BTOG. Once it started making that noise I wanted to see if that might be what was causing it so I changed back to the 5w-40. I was also concerned that on the bottle of Mobile1 0w-40 it said "European car formula" on it. It never used to say that so I thought maybe they changed something in it that the LS1 doesn't like.
Last edited by Spink; 04-13-2007 at 11:00 AM.
04-13-2007, 11:38 AM
#4
I just found another post with a video of someone's LS1 doing the same exact thing. Some say it's common and it usually is worse right after oil changes. That's what happened to me as well, oil change and then the noise appeared out of nowhere.
https://ls1tech.com/forums/showthrea...ight=oil+level
https://ls1tech.com/forums/showthrea...ight=oil+level
