Funny you mention this. I was actually going to post about a noise that I had on startup... but here's the thing.. i don't think it's the valves.
I get this ticking sound that appears to be worse when it's cold out (so I'm noticing it more now that it's getting colder).. It sort of sounds like when you put a playing card in the spoke of a bicycle wheel. Now here's why I don't think it's the valves...
1.) It happens only when under load
2.) The frequency (ticks per minute) seems to increase with speed, but not really with rpms. i.e. if I'm under load going up a hill in 2nd gear, and then shift to 3rd, but still stay under load... the ticking doesn't change dramatically (only as I accelerate).. If it was the valves you'd expect that with the drop in rpms from 2nd to 3rd the valves would chatter a slower rate.
My theory, and what I was looking for someone to potentially rule out of corroborate was that it's my guibo. Other symptoms I have are some bucking and "kangaroo-ing" upon dramatic load changes at times. I'm thinking that with the cold and under load the guibo is deforming in a way that somehow causes a tick somewhere in the driveline.
The other thing it could be would be the U-joint in the driveshaft. :eek:
any thoughts? anyone?