W124 - How to adjust the idle speed?

Peter C1974

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1985 W123 230E & 1991 W124 200E & 1999 W210 E240
1993, W124, 200TE manual:

9-3.jpg


How do I adjust the idle speed? Mine is a little low and needs a gentle tweak.

Peter
 

roofless

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w124 e220 estate
do you know what make of carb is fitted
 

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Lift the air cleaner off, and look at the throttle cable where it joins the carb, there is a rotary shaft going through it with the butterfly plate that opens with you operate the throttle cable. Looking at the operating part again there will be an end stop with a screw that is the end stop,by turning the screw in the engine should speed up
 

roofless

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it's not a k-jetronic with that air fillter so i would guess it's the carb
 

5907

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He says it's a 1993, in which case it definitely won't have a carb. It would be a 200T if it did, and would be pre-1990.
 

roofless

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He says it's a 1993, in which case it definitely won't have a carb. It would be a 200T if it did, and would be pre-1990.

but the car in the photo is for sure not a k-jet car ?
 

5907

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but the car in the photo is for sure not a k-jet car ?

I don't know why you think that; to me it looks like any other fuel injected 200/230TE.

If you look closely you can see the Intake air temperature sensor on the air filter housing.
 

roofless

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I don't know why you think that; to me it looks like any other fuel injected 200/230TE.

If you look closely you can see the Intake air temperature sensor on the air filter housing.

so is the fuel metering head ect all under the airbox
 

Number_Cruncher

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1995 W124 E300D TE
>>If you look closely you can see the Intake air temperature sensor on the air filter housing.

And the grommet for the mixture adjustment in the air filter top.

Yes, the metering head is below the air filter.

I had thought that the E in the model designation stood for Einspritz, the German for injection - is that right?

If it's a 1993 car, it will probably have a cat and closed loop fueling control - is the idle speed also controlled by the ECU? (i.e., does this sytem have a rotary idle actuator, or just an auxiliary air valve?)
 

turnipsock

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I don't know why you think that; to me it looks like any other fuel injected 200/230TE.

If you look closely you can see the Intake air temperature sensor on the air filter housing.

I agree.

There should be something on the end of the throttle cable to adjust.
 

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I agree.

There should be something on the end of the throttle cable to adjust.

There early system like on the first injected 107 had a idle adjustment, these are KE without a rotary idle adjuster, these have the large screw just in front of the throttle body.

Cars with a rotary idle control can only be set on STAR
 

GEORGEROV

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Hi Peter, only adjustment you can make if the ancillary components are ok is to the mixture adjustment screw, as mentioned in the top of the air filter, using a 3mm allen key. You need a co meter to make this adjustment.(Halfords have the Gunsons ones for £25 at the moment). Also ensure the air filter is recent and clean.
 

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Hi Peter, only adjustment you can make if the ancillary components are ok is to the mixture adjustment screw, as mentioned in the top of the air filter, using a 3mm allen key. You need a co meter to make this adjustment.(Halfords have the Gunsons ones for £25 at the moment). Also ensure the air filter is recent and clean.

This only adjust the mixture, turn it too far and you will never start the car, its important that no downward pressure is applied to the allen key, as you say with out plugged into a exhaust analyzer almost impossible
 

Smudge

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Some of these cars have a large adjuster screw on the aux air valve you can set idle by adjusting this. On larger engined k-jetronic some jiggery pockery with resistors in the aux. air valve power feed will alter idle speed.
 


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