1990 560sel air mixture setting?
 

i need a site to tell me how to set the duty cycle, i turn the mixture screw but i am not getting any results what can that mean? do i unplugg the o2 sensor for this?

First check the fuses in the OVPR....next, check o2 feed back with and without o2 connected with engine warm....should have steady line voltage at KOEO of 0.5vdc with o2 disconnected on the ECM side of the connector ( fat GREEN wire.).....and an engine running signal with o2 disconnected of around 0.3vdc to 0.850vdc on the thin BLACK wire...with o2 connected the o2 voltage should swing between 0.02vdc up to 0.950vdc or somewhere in between with crossovers of about two to 5 per second at idle.

Measure voltage with a DVOM with 10 meg ohm resistence.

disconnect the 02 sensor under the passenger floor right? check the voltage in the plugg?

If you wish to adjust the mixture by duty cycle you definitely need to leave the O2 sensor attached.

I'm not sure what isn't working, in a post recently I forgot to point out that one needs to push down on the adjusting device to engage the adjuster. The other issue is that late models that have the led diagnostic on the passenger side mnust have the diagnostics activated to get the duty cycle read out.

to check the duty cycle just put the pins in holes 2 and 3 and turn the key on right andf for the other reading at 25oo rpms of course turn the car on

It is explained in this link for your specific engine:
http://www.landiss.com/mixture.htm

you'll need a CO tester to be able to adjust the right amount of air versus fuel.

Or, do it the Really nice way (my pref'd method)...install another O2 bung in the exhaust, find someone that has a 5 wire wide band O2 sensor and hand held meter. Drive/test w/ that and you'll be able to dial in your mixture as close to ideal as possible.

I'm partial to this companies products:
http://www.innovatemotorsports.com/

For those looking to get Peak performance I'll rent the dyno for an hour and tune accordingly.

Jonathan

The absolute mechanism to adjust is the proper electronic means. Using a CO meter is archaic and will not get even close to the results done properly.