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Hi all ive just taken over a 1996 honda civic coupe and it starts to valve bounce at about 5000 RPM. Its starting to become very frustrating on long drives - being auto it drops back a gear going up big hills or trying to overtake and this is where its occurring most. The car also back fires when i take my foot off the accelerator for more than 5 sec - not sure if its related in any way. What would cause this and how do i fix it? Any suggestions would be greatly appreciated