Need help IDing electrical components-late E500

[BlitzenBenz]

Greetings,

Does anyone here know the function of these components? I believe the one with the wire-tied dial allows for low quality fuel by modifying the ignition timing, but that is a guess. Very interested to know what they do. Car is a ‘95 Euro model. Thanks!

 

[gsxr]

The wire-tied trim plug R17/2 is for setting the fuel injection maps, see below.

Ignition timing maps are adjusted with different trim plugs inserted into the EZL. Standard is a green #2 plug.

The other item (black cylinder) is capacitor C2 for electrical noise suppression for the CAN module power supply.

 

[BlitzenBenz]

I’m humbled, I have wondered about these things for years so many many thanks! I’ve never adjusted the thing, Really makes me wonder how performance would change if one were to modify the fuel map…

 

[gsxr]

I’m humbled, I have wondered about these things for years so many many thanks! I’ve never touched the thing, Really makes me wonder how performance would change if one were to adjust the fuel map…

I did a lot of research into this years ago, wondering if there was some special magic powers to be unlocked with different maps. AFAICT most cars are set/delivered with the max-power settings for both fuel & ignition, and the adjustments are likely only for de-tuning in certain regions. The factory docs are really, really vague on the fuel map settings though. Basically zero information about what each number on the dial indicates.

 

[BlitzenBenz]

That is all very helpful information, thank you! I'd love to give you a shout out in the auction comments (since I am parroting your intel...), but as I understand it's preferred this board not be referenced over there.

Just please know that your assistance in helping me better understand some of these lesser known systems is truly appreciated

 

[gerryvz]

Non-US cars have those dials and did for many years to account for varying qualities of fuel available in markets where the MBs were sold (and/or would have been used). My 1995 gray-market G-wagen with M104 engine has both the dial, as well as the large black capacitor.

 

[xfadmin]

Is the OP on this thread the same guy who used to go by the name "Michael" on MercedesShop.com and/or Benzworld many years ago?

 

[gsxr]

The EZL trim plug was meant to adjust for fuel quality (lower octane).

I still don't fully understand the different LH fuel map options, which were not available for USA models.

 

[gerryvz]

The EZL trim plug was meant to adjust for fuel quality (lower octane).

I still don't fully understand the different LH fuel map options, which were not available for USA models.

Fuel injection and ignition maps are inter-related, and thus the resistor settings for each are used together based on the fuel quality, driving application and location. There are fewer ignition (EZL) resistor settings, per the cap numbers, available than there are with the fuel injection resistor settings.

 

[gsxr]

Fuel injection and ignition maps are inter-related, and thus the resistor settings for each are used together based on the fuel quality, driving application and location.

But the EZL trim plug is meant to be swapped out based on available octane (worldwide), while the LH fuel trim is safety-wired with a tamper seal and not meant to change (and, is fixed to a single map in USA).

@Klink?

 

[asultan]

Performance Upgrades

Granted the link above is specific to the M103, but the general idea applies