couple of newbie questions

[Riverden]

Hi All,

Have just picked up a 98 156 1.8TS which I
am loving at the moment. However over the
last week the car occasionally doesnt
start 1st time. When I start up it
sometimes makes like a hissing/gassing
noise (its hard to explain), but the
engine doesnt even make an attempt to
start. At 1st I thought I wasnt allowing
time for the Code to clear and hence car
wudnt start, however this morning I made
sure the Code light had dissapeared,
started her up and noise returned. When I
return the key position to stop and
restart, starts up no problem (always
starts on 2nd attempt). just wondering if
anyone had a clue...as I say the noise
sounds like air going thru (hiss/gass) and
engine doesnt make attempt to start (some
sort of immobiliser thing??).
I am using the master key which is
celotaped at the moment (I stepped on it)
so I dont know if that could have a
negative effect. I need to get the other
keys coded pronto!

Another thing while Im posting is that
when car's cold and for example I leave
the car park at work in 2nd, if I hit the
clutch the rev's shoot up quickly and then
return to normal (foot off gas obv). This
is only in the first few minutes and only
when press the clutch. The car revs
constantly just under 1000 on the dial
(900+ or -) all the time so its not like
it misses a beat or anything, just revs
shoot up when press clutch when cold. Is
that normal ?

Not 2 good with car's so any replies
appreciated b4 i take to garage.

TIA