What did I do now?
Thread Starter
Pro
Joined: Apr 2008
Posts: 610
Likes: 2
What did I do now?
Ok, so this winter I took the valve covers off and repainted them. Changed the oil the whole nine. Just started driving it this weekend and today to work. That's when I heard it. When I let off of the gas I hear this rattle sound in the engine. 
I don't know what it could be. Please make it go away. Help 
It sounds like it is inside the valve covers. It didn't make this noise before. Just when I thought I was ready for the summer. I was so pumped up about driving it.
1987 L98 thanks for your help.
I don't know what it could be. Please make it go away. Help It sounds like it is inside the valve covers. It didn't make this noise before. Just when I thought I was ready for the summer. I was so pumped up about driving it. 1987 L98 thanks for your help.
Instructor
Joined: Mar 2009
Posts: 136
Likes: 0
From: South Carolina
We really need more information to come to a better consensus, but I'll take a stab at it.
First off, how loud is the noise? Is it consistent with your RPMs? Your noise may be your lifters, which isn't that loud, which is pretty common. Could be that you dropped something onto the heads and bouncing around on your rockers (unlikely). Also could be that your rockers are hitting your valve covers which would be pretty loud and noticeable. Or maybe when uninstalling and reinstalling you bent the pushrods by mistake.
Let us know, best of luck.
First off, how loud is the noise? Is it consistent with your RPMs? Your noise may be your lifters, which isn't that loud, which is pretty common. Could be that you dropped something onto the heads and bouncing around on your rockers (unlikely). Also could be that your rockers are hitting your valve covers which would be pretty loud and noticeable. Or maybe when uninstalling and reinstalling you bent the pushrods by mistake.
Let us know, best of luck.
Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
First you need to localize where the sound is coming from left, right, front, rear, then determine if it’s internal or more top end, you can use a long hose or a long pipe as a stethoscope to help find it. It also could be a rattle coming from your pre cats in the exhaust seeing how the noise is on deceleration these are know to come loose inside the pipe and rattle around. If you didn’t change the rockers I don’t see why they would be now hitting the valve covers. Good Luck
Thread Starter
Pro
Joined: Apr 2008
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Thanks, for all your ideas. I am trying to retorque my valve covers, I thank you were right. I think the rockers are hitting the valve covers too. If this doesn't work I will try all of your other ideas. Save the wave.
Advanced
Joined: Feb 2009
Posts: 74
Likes: 0
From: Acworth Georgia
Are you certain it's coming from the valve covers. Re-installing valve covers is pretty straight forward. I doubt you did anything to cause it. I thought I had a terrible bottom end noise and I finally traced it to the belt tensioner. It would only knock on the stop flange at cold start.
Good luck
Good luck
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Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
did you put the valve covers back on the same side as they came from ? the baffle may be just contacting a rocker . unlikely but if something under there is touching if you pull of your covers and look underneath u can usually see the mark. normally if something touches under there it never stops so you can hear it going bang bang at idle . maybe worth a look though. just seems coincidental thats all you have done apart from oil and it has started.oh and recheck your oil level.
Last edited by gingerbreadman1977; May 20, 2009 at 12:03 AM.
Thread Starter
Pro
Joined: Apr 2008
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Thanks for all your help and suggestions. The problem is fixed is was the rockers hitting the valve covers. I just want to let you know that I fixed it and had the valve covers torqued to tight. Thanks again all.
Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
Thread Starter
Pro
Joined: Apr 2008
Posts: 610
Likes: 2
The FSM says 50 in. lbs. So that's what I did. But that wasn't the problem. 
I think it is in the pre cats like floridamale suggested. Does this mean my exhaust system is screwed. What a terrible excuse to install a new Corsa exhaust. Yeah! Or can I just fix the problem. I'm putting it up on the ramps again Saturday. What should I check for? I guess just get underneath and listen to see if that is where the sound is coming from. I don't think it is coming from the belt tensioner but I'll check that too. Any suggestions just let me know. I am very particular and rattles make me nuts. I can't handle it. It makes a great machine sound like junk. Please help. Thanks again, Todd
I think it is in the pre cats like floridamale suggested. Does this mean my exhaust system is screwed. What a terrible excuse to install a new Corsa exhaust. Yeah! Or can I just fix the problem. I'm putting it up on the ramps again Saturday. What should I check for? I guess just get underneath and listen to see if that is where the sound is coming from. I don't think it is coming from the belt tensioner but I'll check that too. Any suggestions just let me know. I am very particular and rattles make me nuts. I can't handle it. It makes a great machine sound like junk. Please help. Thanks again, Todd