Name this noise.....
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Name this noise.....
I get this every time I give it a small amount of gas after the transmission has gone into OD. It only does it after the trans temp is up to about 160 or higher. I was thinking exhaust rattle but why wouldn't it do it cold? Is it the torque converter?
The videos are under normal acceleration. The first is with the lens cap off the camera. The second one I left the cap on so you can use your imagination better.
Vid # 1
http://s274.photobucket.com/albums/j...t=MVI_0271.flv
Vid # 2
http://s274.photobucket.com/albums/j...t=MVI_0270.flv
The videos are under normal acceleration. The first is with the lens cap off the camera. The second one I left the cap on so you can use your imagination better.
Vid # 1
http://s274.photobucket.com/albums/j...t=MVI_0271.flv
Vid # 2
http://s274.photobucket.com/albums/j...t=MVI_0270.flv
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
I can really hear the engine bog with ~40 seconds left over on video #2(the no pic video). Is the the noise you mean? It is kinda tough to hear with you creaking the leather around on the seat. Sounds like you have decent pick-up still. Maybe clogged/broken cats or pre cats is the noise you hear.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I can really hear the engine bog with ~40 seconds left over on video #2(the no pic video). Is the the noise you mean? It is kinda tough to hear with you creaking the leather around on the seat. Sounds like you have decent pick-up still. Maybe clogged/broken cats or pre cats is the noise you hear.
Might be the cats! But no precats on the '96's. Sometimes it sounds like is on one side of the car then others it's on the other side. Today it sounded like the left side. When I first installed the ECM after getting it reset for the changes with the stall converter and the different gears. I heard a loud pop.....almost like a pistol going off. First the right side popped then a few seconds later the left side popped. I'm not getting any codes so it beats me what it might be. It only started after this gear/stall converter swap.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Any more takers or is the general consensus a rattle in one or both of the cats?
If you can't make out what I'm tryinmg to describe here it is after the car goes into OD.
If you can't make out what I'm tryinmg to describe here it is after the car goes into OD.
Drifting
Joined: Feb 2003
Posts: 1,614
Likes: 163
From: Davis CA
Have you tried a mechanics stethoscope with the engine running? You might hear the sound even not under load with the stethoscope. And you should be able to simulate load against the brake if that is required. Only do this sort of thing if you are absolutely certain that you are doing it in a way that will not harm you or a helper.
Le Mans Master
Joined: May 2007
Posts: 8,448
Likes: 27
From: Valparaiso
wow i can hear that !
is that part of a rotating thing ? do you feel like a light metal part is vibrating
sounds heavier to me,like drive train or something
is the one at 00:24 (no pic video) right ? at 00:40 its comes in and goes
i dont like the sound of it !
is that part of a rotating thing ? do you feel like a light metal part is vibrating
sounds heavier to me,like drive train or something
is the one at 00:24 (no pic video) right ? at 00:40 its comes in and goes
i dont like the sound of it !
Melting Slicks
Joined: May 2007
Posts: 2,171
Likes: 1
From: Warwick RI
If you can only get it to rattle in OD than it would stand to reason that it is not a cat or heat shield problem. Get it to rattle and step lightly on the brake, there may be an issue when the TC locks. If it goes away as soon as you touch the brake it is the TC (electrical interrupt to the lock circuit). The video is hard to tell where the noise is from so that would be the reason for so few replies.
My money is not on the cat because of the OD only thing
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Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Have you tried a mechanics stethoscope with the engine running? You might hear the sound even not under load with the stethoscope. And you should be able to simulate load against the brake if that is required. Only do this sort of thing if you are absolutely certain that you are doing it in a way that will not harm you or a helper.
If you can only get it to rattle in OD than it would stand to reason that it is not a cat or heat shield problem. Get it to rattle and step lightly on the brake, there may be an issue when the TC locks. If it goes away as soon as you touch the brake it is the TC (electrical interrupt to the lock circuit). The video is hard to tell where the noise is from so that would be the reason for so few replies.
My money is not on the cat because of the OD only thing
My money is not on the cat because of the OD only thing
So far no problems changing gears. As a matter of fact it's the best it's ever been. The stall and gear change have bought this car to life.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
If you can only get it to rattle in OD than it would stand to reason that it is not a cat or heat shield problem. Get it to rattle and step lightly on the brake, there may be an issue when the TC locks. If it goes away as soon as you touch the brake it is the TC (electrical interrupt to the lock circuit). The video is hard to tell where the noise is from so that would be the reason for so few replies.
My money is not on the cat because of the OD only thing
My money is not on the cat because of the OD only thing
So, my next step would be what? Is the interrupt in the converter? If so I'll be getting another one. Or should I just take it to a transmission shop and let them check it out? That stuff is way over my head! Thanks a lot!!!
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I have the stock one. A performance one is what I have now. Got it from Pete K. 9.5/2600-2800 stall. When I made the swap from the 2.59 gears to 3.07 and changed converters is when all this noise stuff started. I guess that was about 5 weeks ago.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Your absolutely correct. My bad and apologies. I'm just thankful I'm getting closer to a solution, thanks to Iroc57!
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Sorry for the background noise. I had the camera just resting on the center console in the lens on video.
Might be the cats! But no precats on the '96's. Sometimes it sounds like is on one side of the car then others it's on the other side. Today it sounded like the left side. When I first installed the ECM after getting it reset for the changes with the stall converter and the different gears. I heard a loud pop.....almost like a pistol going off. First the right side popped then a few seconds later the left side popped. I'm not getting any codes so it beats me what it might be. It only started after this gear/stall converter swap.
Might be the cats! But no precats on the '96's. Sometimes it sounds like is on one side of the car then others it's on the other side. Today it sounded like the left side. When I first installed the ECM after getting it reset for the changes with the stall converter and the different gears. I heard a loud pop.....almost like a pistol going off. First the right side popped then a few seconds later the left side popped. I'm not getting any codes so it beats me what it might be. It only started after this gear/stall converter swap.
Drifting
Joined: Mar 2008
Posts: 1,756
Likes: 0
From: Wichita KS
I hear a blow-torch kind of sound. My Suburban was making a similar noise, like high-pressure air blowing out the exhaust under acceleration.
I just wonder if it's the air injection pump coming on and the cats are burning off.
With headphones on, it sounds like the trans is unlocking the converter. You don't show the tach so we can't tell if there's an RPM change. I have high-flow 3" cats on my car. They rattle when the car is at idle. Sometimes only one does, sometimes both. It's not doing it now....
I just wonder if it's the air injection pump coming on and the cats are burning off.
With headphones on, it sounds like the trans is unlocking the converter. You don't show the tach so we can't tell if there's an RPM change. I have high-flow 3" cats on my car. They rattle when the car is at idle. Sometimes only one does, sometimes both. It's not doing it now....
Last edited by Ryan59; Oct 11, 2008 at 06:27 PM.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I hear a blow-torch kind of sound. My Suburban was making a similar noise, like high-pressure air blowing out the exhaust under acceleration.
I just wonder if it's the air injection pump coming on and the cats are burning off.
With headphones on, it sounds like the trans is unlocking the converter. You don't show the tach so we can't tell if there's an RPM change. I have high-flow 3" cats on my car. They rattle when the car is at idle. Sometimes only one does, sometimes both. It's not doing it now....
I just wonder if it's the air injection pump coming on and the cats are burning off.
With headphones on, it sounds like the trans is unlocking the converter. You don't show the tach so we can't tell if there's an RPM change. I have high-flow 3" cats on my car. They rattle when the car is at idle. Sometimes only one does, sometimes both. It's not doing it now....
Melting Slicks
Joined: May 2007
Posts: 2,171
Likes: 1
From: Warwick RI
You may have nailed it. I took it out and got it into OD and gave it a slight amount of gas. The noise started......I tapped the brake and it immediately quit and went into 4th gear out of OD.
So, my next step would be what? Is the interrupt in the converter? If so I'll be getting another one. Or should I just take it to a transmission shop and let them check it out? That stuff is way over my head! Thanks a lot!!!
So, my next step would be what? Is the interrupt in the converter? If so I'll be getting another one. Or should I just take it to a transmission shop and let them check it out? That stuff is way over my head! Thanks a lot!!!
Next step would be to call pete K and see if that would be the issue. He knows trannys so it is a good bet that he has seen this before. If you put the converter in before you can do it again, if not you may have to pay someone.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
What you felt was the lock releasing, you were always in 4th (OD). I use the term interrupt to describe what you are doing to the electrical circuit not an actual piece in the tranny. I believe that the TC lock is in the converter though.
Next step would be to call pete K and see if that would be the issue. He knows trannys so it is a good bet that he has seen this before. If you put the converter in before you can do it again, if not you may have to pay someone.
Next step would be to call pete K and see if that would be the issue. He knows trannys so it is a good bet that he has seen this before. If you put the converter in before you can do it again, if not you may have to pay someone.
I sent him a PM with this thread link earlier this evening. He's a busy man but has always responded....it just takes a while sometimes.
Can this cause any damage if I continue to drive the car normally? I'm out of town with the car and I need to go home tomorrow, about 80 miles or so.