99 prelude base
50k

recent 5w30 oil change

engine rattles mostly under decel. strange part is that it does it between 1200rpm and 500rpm. when it settles into idle at 5k (when warm) the rattle goes away. it's starting to do it during accel or even constant rpms. on cold idle it doesn't happen because idle is around 1200-1300. lately it doesn't happen at all when the car is cold. it seems to be getting slightly worse when warm.

sounds too deep to be a "tick". almost sounds like a rattling heat shield but it seems to be coming from internally and from the top of the motor.

car seems to run fine.

any help would be greatly appreciated.



Modified by juandela at 4:45 PM 9/29/2006

 

try to get your valves adjusted... and check your front and back heat sheild on your header... if you have stock headers

 

yup, stock headers.

i'll check that out.

does the valve adjustment theory conform with this strange range of rpm's that produces the sound? i would think that mis-adjusted valves would make a noise at all rpms.

thanks for the help.

 

not always... i've had a valve sound at idle and then when driving and let out it would do it but when reving up it wouldn't.. sometimes...

 

okay. interesting.

just talked to the local honda service manager and he's at a loss.

he said, though, he doesn't see many timing chain tensioner issues in this motor. strange, here in internet-world i see it talked about as it is were common.