W124 - How to adjust the idle speed?

Peter C1974

Senior Member
Joined
Feb 20, 2009
Messages
967
Reaction score
14
Location
Buckinghamshire
Your Mercedes
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

Senior Member
Joined
Mar 30, 2007
Messages
1,952
Reaction score
1
Your Mercedes
w124 e220 estate
do you know what make of carb is fitted
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
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

Senior Member
Joined
Mar 30, 2007
Messages
1,952
Reaction score
1
Your Mercedes
w124 e220 estate
it's not a k-jetronic with that air fillter so i would guess it's the carb
 

5907

Senior Member
Joined
Feb 12, 2009
Messages
124
Reaction score
0
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

Senior Member
Joined
Mar 30, 2007
Messages
1,952
Reaction score
1
Your Mercedes
w124 e220 estate
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

Senior Member
Joined
Feb 12, 2009
Messages
124
Reaction score
0
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

Senior Member
Joined
Mar 30, 2007
Messages
1,952
Reaction score
1
Your Mercedes
w124 e220 estate
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

Senior Member
Joined
Oct 10, 2007
Messages
1,806
Reaction score
2
Your Mercedes
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

Senior Member
Joined
Sep 14, 2004
Messages
1,479
Reaction score
0
Age
63
Location
Port of Menteith
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.
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
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

Senior Member
Joined
Nov 3, 2006
Messages
273
Reaction score
2
Location
Morayshire
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.
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
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

Senior Member
Joined
Jun 16, 2006
Messages
151
Reaction score
0
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.
 


Text: V4B offer competitive leasing deals across the Mercedes Benz range, we have excellent knowledge and experience on the Mercedes product and we pride ourselves on providing excellent customer service.
V4B
Top Bottom