Am encountering intermittent, very loud noise that sounds like a baseball card in the spokes of a bicycle.

It only happens at highway speeds, i'd wager above 3500rpm, where i'm cruising at about 110km/h

if i let off the gas and coast for a while, it usually slowly gets quieter.
If the car gets parked for any amount of time, it gets quieter.

got it to happen down to idle and pulled over and tried the stethoscope.

the only place i could sort of hear it was on the fuel pump?

timing cover was quiet, as were all the points on the head i tried.
did not try distributor i don't think.


i'm beginning to suspect potentially it's a meshing/input shaft noise on the tranny.

It almost sounds vaguely reminiscent of a rod knock.

I do have oil pressure and good oil in there, so doubt it would be.

Anyone have any ideas?

Any loss in performance lately? or When the noise is at its worst?

NotHing drastic. Maybe maybe feels like timing gets a little bit retarded

Did you try your stethoscope on the distributor? You might have broken springs on the advance retard weights and they are hitting the side of the casing. Check by feeling how the rotor reacts when you give it a twist, should spring back. A good CLA on it not a bad idea anyway.

It could well turn out to be the timing gear. Sounds vary depending on how it's breaking up. It will usually get you home even if it sounds as if your big ends have gone.