had a spare dk motor that came with the car and refurbed it first,"skipped"the resistance measurements cause everything looked so good in the wiper contact area.that cost me a full day frustrating r&r of both assemblies trying to figuer out what was wrong.on initial start up it ran on one bank only and eml came on,i drove for 100 ft and trans fail safe came on.in my mind im thinking i could have avoided this by letting wuffer who has the knowledge rework these dk's and id be smiling right now instead of feeling like im handcuffed to the stern of the titanic on it's final plunge to the bottom.it ended up being that first motors wiper assembly and i finally worked it out and the car runs beautiful.what i learned is that trial and error is a bad method of troubleshooting on these cars because of the complexity of the prehistoric engine management systems and if you arent careful you could cost yourself 10 time the$ that you are trying to save by doing it yourself.:embarrasm

...ah, yes - and you have no idea what a learning process it will be.

what i learned is that trial and error is a bad method of troubleshooting on these cars because of the complexity of the prehistoric engine management systems and if you arent careful you could cost yourself 10 time the$ that you are trying to save by doing it yourself.:embarrasm

:) You are not alone - but you can be sure, that you´ll get support...

I was searching for days to find out, that I failed with one DK too, tried everything else before, I felt confident to have done everything good...

http://www.cafeamwehrgang.de/fbilder/kohlestreik.jpg


...till I found out - what did I find out?

common problem for first-time rebuilders: getting everything back the way it is supposed to be...

ive only owned this car for about a month and it has never idled smooth or accellerated cleanly til now.DK motors are strange,the symptoms led me to think i had ignition problems so i replaced caps and rotors.no change in the miss,i was about to pull injectors and consider dripping/plugged pintles and then i read the thread on DK motors and figured id give that a try and purely by chance it corrected all symptoms.ive got questions on idle control.i dont see any method of regulated air bypass other than pcv/charcoal canister.how do these cars idle?.is it all controlled by DK throttle valve?is there supposed to be a high idle effect on initial startup or extended high idle for really cold starts?

YES, the idle and high idle cold start is all controlled by the DK throttles, even the crusie control works thru the EML to the DK throttle. That is why it is important to either NOT remove the wiper when cleaning the brushes, or, as you know measure the resistance of the closed position and reset the wiper to the original resistance. BTY, if you look at the connector, there is a hole with no contact in it, that is the hole that you can put a hex key in to reset the wiper when reassembled.

any chance of you having access to those dk specs?.i can set them to the values outlined in the diy thread but those arent exact.im hoping that having them equal to each other is most important and that eml can compensate for slight out of tolerance?

Found this on a search. Indicates that the EML "learns" what is open and closed. Or self calibrates.
http://www.fibersonde.com/e31/pdfs/dksync.pdf

LouM...

Found this on a search. Indicates that the EML "learns" what is open and closed. Or self calibrates.
http://www.fibersonde.com/e31/pdfs/dksync.pdf

LouM...


Within reason. The EML program has a limited amount of calibration. If your readings are off beyond a preset amount, you will throw an EML code light, because the compensation "is outside design parameters".

Within reason. The EML program has a limited amount of calibration. If your readings are off beyond a preset amount, you will throw an EML code light, because the compensation "is outside design parameters".ive got three dk motors.two were installed on vehicle.one was a spare that came with the car in a box of robbed parts from another car that ended up in a japanese junk yard in atsugi.the spare cleaned up perfect and the wiper assembly had no signs of wear at all,the only issue is the closed throttle position is 2600 ohms and wide open is 1440 ohms.i havent measured the ones on the car yet and they really needed cleaning up,the brushes were so caked with dust they had no spring pressure against the comutator at all.i only know that the spare motor will not run on this car at all.instant eml light.you can only adjust the resistance approx 150 ohms by clocking the wiper.these motors must be year specific or come in matched sets?

Slight Hijack, Sorry!
Does anyone know if 1989 750 DK's will work on a 91 850? Got a pair for free and wanna know if there looking for Ebay or keepers, Tia!

Slight Hijack, Sorry!
Does anyone know if 1989 750 DK's will work on a 91 850? Got a pair for free and wanna know if there looking for Ebay or keepers, Tia!


M70/E31 = M70/E32 :)


http://bmwfans.info/part-13541736856/


It fits!

Here is the schematic and specs for the DK motors.

http://www.mwrench.com/Whitepapers/dkspecs/DK1.jpg


http://www.mwrench.com/Whitepapers/dkspecs/DK2.jpg

The DK motors were not paired up at the factory, you should be able to match any DK to another (provided it hasn't been monkeyed with) and it should sync with the other thru the EML.

BTW, the DKs will sync eventually even if you do not do the coast down procedure, just takes longer.

HTH

M70/E31 = M70/E32 :)


http://bmwfans.info/part-13541736856/


It fits!Thank you!--)

ive definitly got a motor out of spec and will not come in as it reads 2600 ohms.ill focus on the two good ones and adjust them to where they should be.i never should have removed the wipers but the grease looked so rotten i had to do it.with these specs i can complete the task perfectly.