Idle RPM

Hi!
Does anyone know (or had the same issue) why in my 2.4 non-turbo C70 engine the RPM goes so low when I press the clutch to stop that already originated the engine to stall?
This is a new thing but always since I remember when I approached a red light for example and pressed the clutch and the brakes the rpm would go low... but nothing too much to cause it to stall. As soon as the car would stop the engine would go back to normal around 900rpm or so ... now it goes really below 500 and up again to more than 1000 and down again to under 500 ... twice it caused it to stall ...
Does anyone have any ideas?
Thanks
FS

[sholtby]

Try removing and cleaning out the idle control valve with WD40.

simon

[warthog]

Hi,

I seem to remember there was someone else a little while ago posting on here that had similar problems. I can't remember the outcome but think there was some talk of ECU programming problems. Anyone remember?

[Chris_Rogers]

Would help to know the year.

If 99+ it sound like an electonic throttle problem.

If earlier, then dirty throttle body & / or idle air valve / vacuum leak.

i had the same symptoms and cleaned the throttle body and idle control valve without any luck but fitting a new maf sorted the problem.

heres the thread: http://www.volvoclub.org.uk/dc/dcboa...ode=full&page=

[SIAMBLUE]

Mine S70 T5 has been doing the same,for about the last 2 weeks,light keeps on coming on(Lambda),
Have had it diagnosed and it is the Barometric sensor at fault,Fuel is going like nobodies business too.

wheres this sensor???

[SIAMBLUE]

These are fitted to the T5,It is mounted on the left hand side of the engine bay as you stand in front of the car,Very near to the windscreen washer top up,Held on by one bolt and has a lead going into it,

[Chris_Rogers]

See also:

http://www.volvoclub.org.uk/dc/dcboa..._id=7304&page=