recently replace the manifold gasket winch I think I am going to have to do again because the gasket is leaking,I also have a rattling noise when i accelerate can this be caused by a manifold leak or is it something more serious.when I am cruising its fine but when i hit down to pick up speed it rattles sounds like you are shaking a can with bolts in it.

could be loose exhaust... a tool left in the vally...

I like the idea of checking the exhaust. Make sure it's all tight, no rattling heat shields, etc.

Did you remove / move anything else during the recent work?

Matthew

Perhaps one of your cats has failed?

no, oil leak it seems that my intake pipes were loose and there was oil in my plenum and i think the oil was coming out of there,but know that's another issue not sure if the rattling had anything to do with this. going to change egr valve as well plenum is off.

Are you sure it's not detonation?

Quote:


That's what I was thinking.......

did plenum and runners to manifold over ,rattling seemed to have stopped I am hoping it was from a vacuum leak car seems to be running ok thanks for all your help

I suspect it was a vacuum leak causing severe detonation... the key to understanding auto repair and troubleshooting is understanding cause and effect... they go hand in hand.