knock in top end

[optimist]

...or at least that's where it seems to be coming from. Haven't driven it in a few days and just went to back it out of the garage to change the oil - started it up and the racket that I've always heard for the first couple of seconds after starting the car, now doesn't go away.

Worn timing belt? It's at 58K and hasn't had the 60K service - I've been putting it off. Any other ideas? I'm making an appointment with the local dealer but I'd sure like to know whether it's safe to drive it to the dealer or should I have it trucked?

Thanks.

 

[Briank]

Do you have oil presure? Timing belt replacment is 6years or 90,000mi so it sounds like you are 5 years past due on that unless it has been changed once b4. I have not heard a NSX clatter on startup so you may have had a problem for a while and it just went from bad to worse. You may just need a new oil pump but it is likely you spun a crank bearing.

 

[sjs]

I don't see how anything like an educated guess can be made without more info and a better description of the sound, or better yet hearing it. If it is the same sound you always hear but now won't go away then it limits the list somewhat. As for a worn belt, that won't cause noise unless the result is that it jumps multiple teeth which in turn causes valves to bounce off pistons. That's noisy, but I’m not suggesting it is your problem. Although you are way over the suggested replacement interval in years and the belt may be ready to break, it should not be worn or stretched enough to cause problems. Not impossible, but not very high on the list either.

Edit: changed "miles" to "years" as I had meant to say.

 

[hlweyl]

"Spun a crank bearing".... ouch. Hopefully not. Could just need a valve adjustment, but I would take it to an expert pronto!

Just to be safe, I would have it towed.