Rattle followed by white smoke!

[quk@sievers.com (Phil Payne)]

In message <199705061925.UAA19012@richmond.premier.co.uk> Mike Walder writes:

> I was driving home on a short run, and whilst accelerating, at about
> 4000rpm, there was a rattle from the engine, followed by a large puff of
> white smoke. No power loss, and the engine is not loosing any water.
> 
> The engine has only previously done this at a steady crusing speed on the
> motorway, at about the same engine speed.  (only rattle is less pronounced
> due to wind noise).

The "white" worries me, as does the "no power loss" - otherwise, it sounds like 
an overfilled sump.  "White" and "no power loss" is usually coolant leaking 
into a cylinder from a bad head gasket, but it's not as intermittent.  In such 
cars, the exhaust has an acrid smell (provided there's antifreeze in the 
system).   

> The engine will smoke alot if I engage a low gear down a long hill, or
> similarly engine braking. Also at about 4000rpm.

Probably valve guides.  Head off and replace - not viciously expensive, but
not especially cheap.
 
--
 Phil Payne
 phil@sievers.com
 Committee Member, UK Audi [ur-]quattro Owners Club