Omega 2.0i 1995 - tickover problem revs high then stalls

Hi

hope someone can help by either knowing what may be wrong or could possibly
have experienced the problem before..

essentially the situation is like this - every now and then the revs have
hunted up and down when the car has been stationary but this has never been
consistent and easily put up with..

But today the engine has started behaving very oddly - at tickover or for
instance coming to a stop at junction lights etc... the engine ticks over
very highly at about 2000 - 2500 revs and then suddenly drops right down
momentarily to about 500 and then a split second later stalls completely..


I tried looking under the bonnet and the only odd thing I noticed was that
the electric fan for the radiator was running despite the temp sensor on the
dash reporting that it was only just warm.

to negate that I disconnected the fan but to no avail - same symptoms

Only other thing I noticed was the smell of something either burning or
overheating - it smelt oddly like solid state components melting (worrying)
but I can't really put my hand on my heart and say that this isn't one of
those odd smells from a running engine - this engine has always smelt
strange when running for as long as I have had the car..


does anyone have any experience with a problem like this? I hope so
otherwise it's going cost me to just have it plugged in to find out and even
then a diagnosis is not guaranteed (

 

sound like the idle speed sensor.,

there r past msgs which detail it's replacement & location.
not too diff to do

mike

 

I have exactly the same problem on my vectra 2.0. It is the idle
control valve on mine. It does the hunting and strange revs and
stalling thing.

It costs me £15 to get the idle control valve and some pipes cleaned
out, but the problem comes back after a couple of months.

bob

 

My Mv6 was doing somthing similar before the dis pack went... sorry







RSDesigns

 

I bought one of them error code analysers from halfords and it did indeed
report that it was the idle speed sensor - looking into getting it replaced
now..


Fabs'

 

you say you get the pipes cleaned out - do you have to go to a vauxhall
dealerto do this?

Fabs'

 

Scuse my ignorance but what do you mean by the DIS pack

I'm guessing Injection system or distributor or something?

Fabs'

 

I had it done at a local garage. It comes back again after a few months
though. Something to do with the way fumes are extracted from the lower
part of engine, to be put back through the air intake, and the pipes and
valve get all gummed up.

It sounds like (from your other post) it is the idle speed sensor in your
case.

Bob