where is idle speed adjustment on w124

[beeper]

Hi all,
Does anyone know how to adjust the idle speed on my w124 1991 230e.
I looked in the workshop manual and they showed an indent under the aircleaner! which you shove a screwdriver into, blowed if i can find it.
I had a small problem in France last week, after a 430 mile journey the car just died and would not start. I was recovered to a merc main dealer and they had it for a couple of days and seemed to have fixed the problem. new fuel filter,plugs and a lot of diagnosing.Still don't know exactly what they did!! It got us back to blighty but has this annoying habit of high revs in neutral hence my query.
Hope someone can help me.
ps the car has now done 203,000 miles with very few problems up till now.
Thanks

 

[wscheffer]

Electronic Idle Speed Control

Engines with electronic idle speed control can not be adjusted.

Engines without the electronic idle speed control is adjustable by a idle air screw located under the air cleaner housing.

My bet is that yours is electronically controlled and can not be adjusted.

 

[kth286]

beeper

Yours is not an electronic engine so you do have an adjustment, but with the fiddling by the technicians I guess a vacuum pipe has come loose or torn/holed somewhere, so have a careful look around at all pipes.

 

[beeper]

Hi Is the adjustment through the hole in the middle of the air cleaner
Beeper

 

[television]

this is a change of year, do not touch the one in the standpipe,

Do you have a plug on the air flow sensor, thats the round top where the filter clips on

 

[Ian B Walker]

Hi Is the adjustment through the hole in the middle of the air cleaner
Beeper

No that is for the mixture settings. If your air cleaner does not have a hole in it, then you has a cat engined car and its electronically controlled. If there is a hole then its non cat. The adjustment screw is (standing in front of the radiator) below the left hand side of the air cleaner at the bottom (just under the base) Hope that helps

 

[wscheffer]

No that is for the mixture settings. If your air cleaner does not have a hole in it, then you has a cat engined car and its electronically controlled. If there is a hole then its non cat. The adjustment screw is (standing in front of the radiator) below the left hand side of the air cleaner at the bottom (just under the base) Hope that helps

Ditto!

 

[beeper]

Hi again, Yes my car does have a cat and a hole in the cetre of the air cleaner, I will look for the adjustment screw as ian says.
wish me luck
Beeper

 

[television]

The idle adjust screw is the large head one the size or a ½p with a slot.
If this does not work, then the switch contacts could be faulty, check that they close with an ohm meter.

 

[kiwi_bloke]

My 92 190E with the 2.3 was electronically controlled, however my 85 was not. If you take the air cleaner off, you will see ICV. Some models had a plastic "knob" on the top that adjusted idle speed.