Re: Volvo 740 erratic idle
"A" <andrew_on_tour@NOSPAM.operamail.com> wrote in message
> Hi Everyone:
> The Machine:
> 1990 Volvo 740 GLT 16v 2.3l
> 4 speed + overdrive (ie stick shift)
> 193k miles, well looked after, used more-or-less daily on a variety of
> short (10 min) and long (1 hour+) runs.
> The Symptoms:
> - On a cold start it is quite erratic when idling - will go between
> ~500rpm and ~900rpm.
> - Initial accelleration from cold start is not smooth, but after a
> minute or so accelleration is normal and smooth, although idling is
> still erratic as above.
> - Having been driven for about five minutes idle is less erratic, though
> still wobbles between ~800rpm and ~900rpm.
> Someone pointed out that it could be an air leak somewhere. Do you think
> that this is feasible, and would it manifest itself anywhere else (eg at
> the air filter?)
> Many thanks for any replies received,
Yeah it sounds like classic symptoms of a vacuum leak, look for any cracked
or disconnected hoses, and carefully inspect the accordian hose between the
AMM and the throttle body.