Rattling noise when accelerating and zooming sound when i go of pedal

civic
honda

#1

I got my head gasket changed out. I heard the noise the day after but the mechanic said it was normal. I know an engine should probably sound smoother than that. I got my exhaust manifold changed out, water pump, thermostat, timing belt changed out too.


#2

When the exhaust manifold was changed, it is very possible that the heat shield located on or adjacent to the manifold was bent, or was not securely re-attached. Luckily, that type of problem is merely annoying, rather than being a functional problem that will affect the engine or transmission.

This is easy for any mechanic to check by putting the car on a lift. However, that is just a guess from afar, and you shouldn’t allow your mechanic to skate away from your complaint by saying that it is “normal”.


#3

Thank you! I’ll check up on that.


#4

could be a cracked flexplate, they rattle


#5

Check for exhaust leaks too. Rat-a-tat-tat and zooming sounds can be caused by that too. But I think the advice giving by VDC above is the most likely explanation. Check the cat heat shield too btw.