BMW 520i e34 M50B20 (no vanos) -1992 idling problems - Problem solved! See description

This is my engine idling after about 30 minutes of driving.
When the engine gets warmed up I get this problem.
*** UPDATE 2016-06-11
After a long time I have solved the problem!
It was the Lambda/O2 sensor in combination with a faulty water temperature sensor ( BMW temp sensor: 13621730034 + 12621710511 ) made the car act like this. After replacement the engine works perfectly and I got a much better mileage after the replacement.
***

[@axzell2]

After a long time I have solved the problem!
It was the Lambda/O2 sensor in combination with faulty water temperature sensors ( BMW temp sensor: 13621730034 + 12621710511 ) made the car act like this. After replacement the engine works perfectly and I got a much better mileage after the replacement.

[@gengeez5080]

Change the chock u well end this problem

[@memprus]

Have same problem ('92 M50B20 Siemens M40.0) . Replaced idle control valve, many other sensors, but...

[@GRsavant]

o2 sensor!
(lamda) ( the car runs on limp when you pulled the MAF) ignores o2 or maf needs alcohol bath? do the maf clean-up first, then chase the o2.

[@cihangirasi06]

This problem POTANSİYOMETER

[@stinsmeister]

im gonna say idle control valve? my m20b25 had this problem

[@turbidriver69]

someting to share whit us.....my car does the same since 2007 and no solution until now....:(

[@Danijel9616]

ler lauf maybe?

[@MrMengemeto]

this is IDLE motor problem ... just change it ; )

[@servetbulut9800]

What was the problem?

[@axzell2]

It was a combination of 2 sensors. Lambda/o2 sensor and the water temp sensor sending the temperature to the ECU.
Now the car runs smoothly.

[@servetbulut9800]

Lampda = debimetre ?

[@axzell2]

No, the sensor measuring oxygen in the exhaust.

[@servetbulut9800]

Resim ?