mk1 focus bad idle with elec load

[steveo3002]

2004 focus 1600 , it has slightly low idle with no accessories on , with a/c on the idle drops so it can barley stay running and the dash shakes badly

im sure it should have some way of bumping up the idle to compensate for elec load or the a/c , can anyone tell me what/where to look at

no warning lights on and all serviced up to date with genuine parts

[Dr Doofenshmirtz]

Mine does the same - Lots of googling seems to suggest removing and cleaning the idle air control valve should fix it.
I bought a can of carb cleaner the other day, so I'll report back if it does the trick.

The IAC is at the front of the engine - it's the silver unit pictured.

Edited by Dr Doofenshmirtz on Monday 9th May 09:01

[steveo3002]

already tried that...did need a clean but no better

ive sinse had a ford mechanic look at it,if you look between the manifold and engine theres a rubber hose as thick as a finger , watch while someone starts the car , mine partialy colapses and he suggests this is the problem

have ordered one and will report back

[Dr Doofenshmirtz]

Tried cleaning the IAC as well...no joy.
Where exactly is the hose you mention and have you replaced it yet?

[steveo3002]

its hidden under the inlet manifold ...you can just see the end of it peeking out in your pic, you will need some extra long pliers to change it

i replaced it , £15 from ford , disconect the battery for 10 mins so the ecu can relearn , its improved the idle a bit but not fixed

next step ive ordered and idle valve from ebay...see how that goes

[steveo3002]

http://thumbsnap.com/Y28o6mNG

like so..peek under the inlet and you can just about see it , it has 3 ends

[Dr Doofenshmirtz]

Keep us posted.
The other thing I've read that can cause it is the coil pack.

[steveo3002]

righto

new idle valve fitted (£20 ebay) , throttle body off for a good clean , battery disconected for 10 mins for a re learn

its idling much smoother , no fluctuating and it drops much smoother when coming to a stop

BUT the idle still drops to low with the a/c on so no harm done , feels like it needed the above doing anyway but my problem is still there

[Peanut Gallery]

Not that this will help, but, I have the 2006 Focus, and when the AC is fully charged I can see and feel the revs rise by about 200 rpm when the AC is turned on.

I also had the AC on for so long that when I turned it off the idle went lumpy, within 5 mins this had settled out, but I did notice it!

[steveo3002]

yep as you would expect...revs rise to cope with the added load

these were as common as muck but i dont seem to be able to get much diy help anywhere

[Peanut Gallery]

Wild shot in the dark here - have you tried disconnecting the electrical contact with the idle control valve, seeing if the car will start, and if you have the same idle issues? - part of me feels that the idle control valve is not being told to increase the idle when the load is applied, but how to search for this I do not know.

Another thought, would a code reader show that the ecu is trying to increase the revs when on load? - is it is trying to increase the revs, but not being able to, or if it not detecting the revs dropping?

[steveo3002]

yeah i guess if its the same with the idle valve unplugged then its not getting its signal

with the a/c off ...you can see that something is stabilising the idle if you put the lights on for example it seems to cope , just the a/c is too much load

[bulk66]

Did you get anyware with this mate I have exactly the same problem and have changed all the same parts.