Lambda value at AU too high BMW 116i

Question

Hello everyone, I am currently not getting an AU with my 116i EZ 2010. Lambda value too high, this is 1.6 and higher, engine does not stop. According to TÜV, it runs like clockwork. No error in memory. Since I only drive a short distance (not 10 km to work), I should take a freeway trip before I change everything. I did this on Tuesday. To Göttingen and back, a distance of approx. 40 KM. Unfortunately speed limit 120. On Wednesday again Kassel-Warburg, here higher speeds. Then immediately from the Autobahn to the TÜV. Again nothing. Unchanged values. Today in a workshop, everything tight, which probe is possibly broken, is the question. He told me to use V-Power and injector cleaner?

Do you have any ideas?

PS: In November 16 the car got a replacement engine on goodwill due to the timing chain problem.

Answer 1

Often the probe is not defective, either the mixture is too fat or too lean.

Mixture to lean: (probe in the minus range)

The cause is then that the engine draws secondary air. Either through a hose or from the suction bridge, this is then sucked in, not detected by the LMM and then such malfunctions occur. If these values ​​are then implausible, the control unit may report LMM defective.

Mixture to fat: (probe far in the plus range)

An injector is probably defective. Your value was +1.6. Too much fuel is injected and the control unit may report a fault.

By the way, there is also a sensor behind the cat to check whether the cat converts the pollutants correctly. The compares the values ​​with the first sensor. Also known as MAP sensor / suction pressure sensor / differential pressure sensor. Also check here whether it is OK ...

Answer 2

NOx sensor defective is a known problem. Then you will not be able to complete the exhaust gas analysis because your exhaust gas control will not work. More fuel, less power and stuttering can make itself felt.

Replace the NOx sensor (fortunately it is relatively cheap in the bay) and then a desulphurization trip for the sulfuric catalytic converter does not include 120 km / h in 5th gear for 30 minutes ...