Help DIY a rough idle/hesitation + engine cut on high RPM
2005 E55, engine was re built 4000+ km ago,
Since day 1 engine had rough idle, symptoms was on startup engine runs smooth and wont shake, after several seconds it beings to shake slowly, on obd there was no misfire on cylinders,
Anyhow, after passing the 1000km for first service, i i notice that previous owner had a wrong fuel filter installed that isnt compatible with the newer model fuel pump, new fuel filter installed, fuel pressure got to normal range, butt issue is still there,
We suspected that injectors was bad, so we sent them for a shop to check them, they were bad, all got cleaned, car idle got slightly better, butt still a bet rough on idle + cuts on high RPM.
Anyhow, on my obd i will always get a misfire code on 1 bank after that cut happens.
We suspected that there was a bad coil, coils been replaced, car got better but still facing the same issue.
I noticed on my OBD
LTFT on the same bank with misfire codes has a high negative number -16 to - 19 and once on WOT it will drop to -1.6 or within 5 range.
Any suggestions ?
Today ltft got even more to -21 😅,
I tried to WOT, car ran good ltft on both banks immediately got to 0, then ltft 1 is -6, ltft 2 -21
After couple sec's car got misfire
Shutted car down then start back, car ran normal again.








