my 1.8 zetec hisses after its turned off...
for about 5 secs. worried it might be the pcv valve. any ideas?

Is it the actually from the engine?

Mine gargles a bit from the expansion tank when i first switch off.

cylinder decompressing?

leaking servo? - is it a sucking noise?

its a blowing noise. engines done less than 40k so cant think it would be the cylinder. will investigate the seal on the expansion tank lid. thanks

My RV8 hissis for 5 or 6 seconds when turned off simply because I run a PCV system that give me a very low pressure in the engine block (stopped all oil leaks).

My hissing sound is air going in throught the small breather hole on one of the rocker covers.


Paul

Dont know much about zetecs but if they run a PCV system may be connected.

having investigated further. The noise is coming from the crank ventilation hose. which is connected, via an in line filter to the air box. it blows during running, but then sucks after shutoff, this is normal?