LZH

Since I've had my Black Series, I've had a few CEL's. The first was for a bad cam position sensor which was easily fixed with a new sensor. The second was for a bad purge valve that apparently was causing problems when the fuel level would go too low and the under hood temps were high. Apparently these 63 motors are generating some very high under hood temps that are causing some of the delicate sensors to malfunction. Anyway, they replaced the purge valve with an "optimized" purge valve and I haven't had a problem since.
A few days ago the CEL came on again, and I just so happened to be near the dealer. So, I dropped it off and these are the codes that it threw:


0745 - fuel adaptation enrichment is above the permissible limit
sub code 2091 - mixture in right bank is too lean when idling

They have checked everything and can't figure out what is causing the problem. The only mods I have are phenolic spacers and carbon filters removed. I was hoping someone might have had this problem already and could perhaps shed some light. The shop foreman is the only guy at the dealer I trust to work on my car and he is an older guy that knows everything about AMG's. But, this one has him stumped. Any thoughts or suggestion would be appreciated, and TIA.

jrcart

Luke, that just means FLOOR IT...have you been sissy driving again? JK, I have not had any trouble at all with mine and have driven hard in some extreme heat, we get 90-100 temps here in July and August. I'll keep an eye on it though, thanks for the heads up.

Vic55

FWIW on my CEL (997TT):

left bank lean mixture at idling

yielded a vacuum leak with one of the plenum hoses.

aleksandar1099

Cool new Sig Vic!
Sorry for the OT!

LZH

Thanks Vic, I'll have them take a look.

Jim - no man, it's always WFO for me dude

C32AMG/02

Bank one O2 sensor has detected excessive oxygen in the exhaust system. ECM is commanding fuel enrichment; MAFS has reached max rich adaptation. Vaccum leak could be one cause, easy to detect by introducing smoke into the engine with a smoke machine, its common automotive diagnostic tool. Upstream exhaust leak, defective O2 sensor, restrictive fuel filter (dirty), Low fuel pressure, defective fuel injectors, defective MAFS can cause a lean code. I can’t believe a MB Dealer can’t diagnose a lean run condition. I would install the original filters clear all codes drive the car recheck for any codes, phenolic spacers or intake could also leak false air, the smoke machine will confirm any vaccum leaks. Good luck.

AMGC43C55

BUSTED!!!!!!!!!!!!!!!!

MHP

Luke,
FWIW, my K&N drop-ins (with stock ECU/TCU tune) yielded the same code.

Ausmbtech

Most likely the manifold gaskets are leaking (phenolic spacers).

Even the std gaskets leak, it's quite common.

There are new gaskets with modified bolts and torque settings.