Odd noises

[tellaux]

I bought an 89 Accord Si around 3 weeks ago and after cruising on the highway for around 15-20 minutes (at say 120 km/h) and then accelerating again, a strange noise can be heard from the engine. It sounds like a can of spraypaint being shaken with a bearing inside. However after slowing down and driving again (say exiting the highway) the noise stops.

This car is automatic and I've had this problem with another auto I used to own.

Any thoughts?

[adams86lxi]

kinda sounds like detonation to me. Try higher octane fuel or retard the timing alittle and see if that helps?

http://www.hastingsmfg.com/Service%20Tips/detonation_and_preignition.htm Theirs a sight on detonation if you wanna read up on it.

[tellaux]

Thanks very much. I'll try the fuel.