Holy crap that scares the poop out of Me. I will stare at that wire for 2 hours before I get guts to cut. lol

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1 - ALT-LIN does disable the amazin' ECO Start/Stop. No programming necessary.

2- By design Voltage swings at least from float to bulk.
That is what's being solved here.

If you don't have engine lag, tranny issues or extreme heat then no reason at all to sway from stock.

I don't see an image at that link... repost?

same as this:
ECU HOMERUN TO ALT VIA LIN BUS

I don't think I have any issues on this platform. It will put down 3.3s 0-60s all day long (although I am usually very selective of when I bring the hammer down) - but free mods are always intriguing .

If you have weak engine throttle driveability then that is motivation to act.

Be sure to match chassis VIN for good color/pin No.

Pulling Alternator plug is a PITA on TT
You have options.

HERE... just got a simple idea for preview:
float your battery, reboot chassis and drive with HL:ON.

-- When ALT is ECU controlled, HL:ON commands a fixed voltage that may helps ECU laggy mixtures.

Monitor voltage on your IC Display.

This is NOT "complete ALT-LIN with ECU/TCU adaptations" but it can help you quickly evidence that your engine responds to better voltage.

Laggy throttle is only at the bottom RPM, not under WOT. although during acceleration ppl have recognized weak fuel delivery.
This benefit throttle control for regular driving. Normal fuel map is busted lean by poor ignition to cause lag.

Makes sense. I have noticed that it can lag a little when leaving the line in casual driving, but it's slight... I have a note in my mind to check the throttle body if I ever take the intercooler off. Maybe the voltage issue is what's really going on. Maybe the monitor will tell?

Yes, now you know! It's not oily throttle body.

Actually the whole fuel map under 3000.Rpm is abnormally leaned out by poor combustions.
How do we know.... because we fixed the root causes.

Do you know battery voltage under WOT ??
Is it the same as stock accelerations when ECU drops voltage?

Try these simple steps here!
ECU self-tuning is very gradual by nature...
Results depend on how lean you begin with.

We are starting to have mounting ways to get stable chassis voltage:

> BASIC/EASY:

1. Headlights: ON !

> HARDER/BETTER:

1. Unplug LIN Bus at ALT
2. Cut the LIN homerun at ECU
3. Switch LIN homerun On/Off
4. De-pin ECU LIN connection

> FAVORABLE OPTIONS:

1. Reboot chassis!!
2. Float main AGM !!

> INTERACTIVE JOURNEY:
All options are incremental to get the most stable voltage.

Your best outcome comes from your experimental choices (just like viscosity)

Best outcome I've experienced being on MOD-4 is:
ALT-LIN + FLOAT + REBOOT

This is a transformation journey to let ECU/TCU re-adapt to each other.

Give it about 1000.Mi to completion.

You know you've got no lag when pressure sensitive throttle skids tires from idle!

Speaking of BATT-LIN, you could also just unplug the battery sensor but it probably doesn't do the same thing, at least not exactly as the ECU still can communicate to the ALT. https://mbworld.org/forums/mercedes-...ml#post9097659

Which engines are yielding the most benefit from this mod? I haven't noticed any lagging throttle witm my M176 V8 TT.

So far M276 engines benefits the most from this mod, not saying the M176 doesn't just that not a lot of people have tried it yet and report back so there is not enough data for the V8s. That said, pretty much all recent MB engines (pretty much any MB engine with the 2 stage valve control solenoid)benefit from the oil pump solenoid mod though.

No lag/less lag is very good news for owners

-- You can get an easy sort of preview without any modifications...

-- Try or keep using the "HL:ON" trick to get stable voltage for best ignition and associated fuel maps improvements.

-- In addition floating your main battery is always a positive step

-- Then monitor IC display to report what Voltage/Amperage :
any voltage variation ?
any throttle improvement?

-- Get the engine used to running "HL:ON" fixed voltage CONSISTENTLY TO ADAPT better voltage.
Notice response improvements?


> M176 EXTREME HEAT... Tstat:
-- This engine is recognized to have extreme heat causing Tstat issues... what makes this worse are POOR TIMINGS causing LEAN Mixtures.

-- Meaning Tstat is the "tip of the iceberg": it does not cause high heat but gets coooked by high heat.
@streborx
-- experiment with better RPM pistons spray cooling pressure (SOLENOID + VISCOSITY)
-- experiment with STABLE VOLTAGE to improve timings.

OK, I missed it. What is HL:ON?

I'm gonna guess headlights on

-- "HEADLIGHTS:ON" cause ECU to command a fixed voltage 14V using stock ALT-LIN.

-- Put up IC Display and monitor what "HL:ON" does to voltage control.


(ALT-LIN mod is the preferred method to gain self regulated fixed voltage)

Thanks. That was my guess for HL:ON, but wanted to make sure.

(Om651 diesel start glow plug answered here)

Just for Cali, I made a modification today. I added a chassis to engine ground strap.

On the strut tower, there are three little holes that I have no idea what they are for. So, I took a 6mmx1.0 tap and threaded one of the holes. I had a 6mm bolt that I used to attached one end of the cable to strut tower and the other end to the timing case near the oil filter. This was a quick job and I may need to change the connections, but I thought for now I would do it and see what happens.

By the way, those were old grounding straps that I had used for an audio system on a past car.

and for Mstr Surya too...
We enjoy reliable GND circuits - Tons of weird electronic problems never to be had
Underated capacitors won't get overheated by significant ripples.


> Fun testing:
During installation... before closing the circuit see if you can light up a sensitive test-light between chassis and engine GND or use a DVM.

A used audio cable might cause strange engine noises for the first 50 miles while all the thumpa-thumpa electrons get flushed out.