joer2001,
I just finished doing that to my car and had the exact same thing happen. But, I noticed that the oil return tube underneath the air cleaner housing was not put in properly. Second I found that the bracket had weakend and was allowing for more rattle. So I replaced the bracket, bought 3 new rubber dampers with heat shields and used pressure washers and lock nuts in the cleaner to hod it down. Also, the positioning of the air cleaner has alot to do with it. I found that by using the front holes vs the rear holes made a huge improvement.
I know it all boils down to idle, so if you have a rough idle, you'll have to check that out. The rack-dampner bolt is a must as is the valve adjusments!
Good luck!
