[Urban]

Hello
I'm diagnosing a 05/2012 f30 328i with n20 engine and following fault code 118402 mixture multiplicative adaption to rich.
Car runs rough especially hot but doesn't count any misfires, has power the problem occurs when idle or under constant load. Multiplicative is between 0.7-0.8.  

First diagnosis ruled out the o2 sensor and pointed toward injectors leaking the ista misfire test only confirmed that several injectors are leaking. Injectors were replaced with a new ones ( correct part number chossen for a EU5 injectors as ista pointed ) this didn't solve the problem.
 
Engine has been rebuild by someone alse so i've checked timing is spot on compression is 13bar on all cylinders cold. I replaced following components from a running cars : MAF, air pressure sensors, o2 sensor, temp sensors, high pressure fuel sensor, high p. fuel pump, throttle. Disconnecting the tank vent and plugin up the hole doesn't help. ECU doesnt seem to be tempered. another set of NEW injectors laying around was put in no luck.

I'm running out of ideas. anybody have some thoughs  ?

[Node]

Well, have you looked at live values? Have you looked at condition of spark plugs (especially their color)?

I would think that if mixture is too rich then either there is too little air or too much fuel. If you replaced that many things then there may be left only mechanical problem. For example too much oil in cylinders. Car can't distinguish burning oil vs burning fuel - too rich in both cases. Hence my question about spark plugs. Are they (at least one of them) oily in any way?

[RocketSurgeon]

This can happen with clogged or melted catalytic converters. Fuel trims go rich, and it's super hard to track down. Apparently you can thread a compression tester into the pre-cat O2 sensor bung. You should have less than 2 pounds of back pressure at like 1500rpm.

[Node]

IMHO clogged exhaust should be seen in live data like too little air mass going in compared to calculated value.

[willisodhiambo]

What are the adaptive lambda values?