Eco mode diagnostics
Not quite what I was expecting.
Last edited by rey_winslow; Jul 17, 2024 at 10:59 PM.




ECO tracks the battery charge level to adjust the ALT Voltage.
Last edited by rey_winslow; Jul 18, 2024 at 10:23 AM.
Thanks folks!




See what range of currents are shown.... lower is better.
ECO stands for "Engine Cut Off".
It's the engine "start/stop" feature.
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Last edited by rey_winslow; Jul 19, 2024 at 07:26 PM.
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You need to know if this is discharge while parked or low charge while driving.
Either way that can leads to experimentally unplugging ALT-LIN control.
That chaos serve as witness of poor CAN-C networking with ESP + CGW for which chassis REBOOT is a temporary fix. Same exact thing thats screwing up our smooth TCU shifts.




-- The IC Display shows battery voltage plus charge or drain currents.
-- Positive currents are battery charge
-- Negative current is battery drain
> GOOD VALUES:
-- The voltage will range from 12.6v to 14.9v according to engine computer control.
-- The current should be less than 25Amps and mostly near 10Amp decreasing.
> BAD VALUES :
-- the voltage swings below 12.4V... 12.1, 11.9V... while driving
-- Currents are higher than 35Amps are guaranteed battery drain issue
> TEST RESULTS:
-- Battery should never see voltage below battery charge value of 12.5/12.6V..... NOT 12.1V!!
-- When charge voltage is switched from 14.x down to 12.6V the battery is used as a capacitor to supply "surface voltage" ... is totally expected.
-- Battery charge controlled by soft-crashed Bosch ECU control may swing below 12.3v with high drain currents greater than 30A up to 90Amp.
> QUICK FIX:
-- This is easily reset with "key cycle" while parked.... stop, lock then unlock, restart!
-- Headlights ON does that very well also.

Last edited by CaliBenzDriver; Jul 20, 2024 at 01:41 PM.




The car ran fine, no rough idle until I got to the same spot where it happened the previous times, very strange.
I get home, turn car off and on, quick trip around the block and no rough idle, not sure what to make of it.
Nothing wrong happen today... stay at it.
Restarting the car reinitializes the charging system. Use this info to your advantage if car begins to drain battery below 11.xV while driving, the park to restart.
If you do this while testing then nothing's going to happen. The CGW needs time to trash COM's between ECU and R-SAM through CGW.
Nothing wrong happen today... stay at it.
Restarting the car reinitializes the charging system. Use this info to your advantage if car begins to drain battery below 11.xV while driving, the park to restart.
If you do this while testing then nothing's going to happen. The CGW needs time to trash COM's between ECU and R-SAM through CGW.
I'm not sure I'd say nothing wrong happened today, the engine idled rough and I didn't see any drain on the battery when it happened.
Thanks Cali.
Last edited by rey_winslow; Jul 21, 2024 at 02:23 PM.




How old are your ignition components:
plugs + boots + coils?




40kMi is really a low mileage for new plugs.
Your 10mn home/work commute trips are super short. Hardly time to fully warm up to operating temperature.
How often do you replace the oil ??
If this V6 NA has been ingesting quarts of thin oil you may have dirty lambda giving you lean misfires.
Use the scanner to read the LTFT's at warm idle.




Twice a year schedule would be better... so long it's not the corner shop 10w30 special and much sooner than every 10kMi.
Presumably your lambda sensors and cats are coated with residues, namely ZDDP/Calcium ashes from "approved oils".
To prevent that condition, your best advantage is to use a lubricant API Rated "SP" in the
Until the pendulum swings back towards new nano ZDDP, the "SP" lubricants are being well reviewed. Who ever found a way to blend in all these mollecules is now printing money.
Heavy duty oil are those able to hold viscosity without concerns... with cost-efficient HDEO putting up with short leaved viscosity "to save gas" is now a choice.

Last edited by CaliBenzDriver; Jul 22, 2024 at 11:33 PM.
40kMi is really a low mileage for new plugs.
Your 10mn home/work commute trips are super short. Hardly time to fully warm up to operating temperature.
How often do you replace the oil ??
If this V6 NA has been ingesting quarts of thin oil you may have dirty lambda giving you lean misfires.
Use the scanner to read the LTFT's at warm idle.
Check for rodent damage, chewed on wires. I would also do the two oil change flush, DO NOT USE ENGINE FLUSH IN THESE ENGINES!
Verify Powers and grounds, by voltage drop tests. Cali can explain the ground situation we all face.
As far as yo yo alternator annd ECO issues, when what ever the PCM is fussing about happens the associated cylinder injector is disabled, hence the rough running, but returns to smooth on restart. The yo yo and eco functions are all disabled including the oil pump solenoid as well during the fault.So don’t waste time on that, once the underlying cause of what ever the computer is not happy about is pin pointed and make necessary repairs, those function should begin to function normally.If not we can diagnose after the root problem has been rectified.
You are going to need wire schematics, service information on the coils, injectors, cam and crank position sensors, as well as fuel delivery and ignition data. With all this you should be able to pin point fault and make repairs.
And it may clear up just flushing engine oil. Short in town trips cause sludge, moisture build as engine cools overnight. If engine is not run long enough to burn off moisture, it attracts spent detergents in oil, and begins to create sludge. Sludge in VVT control valve will affect cam timing, can fool PCM to think ignition misfire.
If you do not have this equipment, befriend someone who does DIY and has these tools, as they should be more than willing to help. Or pay a shop diagnostic time, plus parts and labor for repair. Never confuse diagnostic time with labor, two different operations. But please, do not just start replacing parts, this can cloud the original fault. And I always charged customer for reinstall all original parts before attempting diagnosing the problem, so will any other shop. I’ve seen many replacements cause more problems.Some shops will refuse work if a bunch of parts have been replaced, and some will stick it to you seeing all the new parts. Just keep that in mind, going forward.
Hope this helps.
My yearly maintenance is coming up, should I get the oil change before starting the diagnostics? I think I've got other fluids that need to be changed as well.
Last edited by rey_winslow; Jul 23, 2024 at 11:40 AM.
Now it's saying coil 4 has an issue, so maybe something to work with.
Thanks.






