- Scotty congrats on 5 million!. please answer… my 2010 S550 with 221K miles runs rich and my both bank LTFT at negative 19 I reset the adaption values and went back at decent negative/positve 5% but the car runs so rich That I smelled unburned gas from the exhausts after I drove the car it went back to negative %19 LTFT! And the smell vanished.. the dealer quoted me for 2.5K they said the O2 sensor on both banks are bad and that I need a new Intake manifold and a new purge control valve.. even though the engine is in good condition and my private mechanic said that this BS!. Please help!
You lost me a bit there. You smelled gas in the exhaust, but it vanished. Fuel trims were rich, then normal, but right now they're rich?
And now you have a mechanic working on it? So is he going to fix it? Does he have a diagnosis?
The smell vanished because the computer cut the fuel to run leaner but my mechanic couldn’t fix it he said the dealer are liars nothing wrong with intake.. it went normal(LTFT) because I reset the adaptation values
You mechanic couldn't fix "it". Even though he has no idea what's wrong, he thinks the dealer is lying.
But your fuel trim is normal.... So problem solved I guess.
My friend… The LTFT is now -19 it went normal for a small period of time because I reset the adaptation data.
Oh... you are you mashing sentences together without periods, and telling the events in reverse order. I'm having a super hard time understanding what is going on.
So I think the engine is running rich (which is the first thing I asked.)
See if the plugs are wet. Graph the O2 sensor voltages to see if they're working.