Intro to Mercedes 63 AMG (ME97AMG) Tuning
Before you begin tuning these vehicles, here are some tips you may find useful:
The existing calibration on the ECM cannot be read. You are provided with a stock file for your vehicle every time you attempt to read it.
If you get a definition failed to load or checksum error, please email us that file and we will add support for your vehicle as soon as possible.
Understanding variant coded parameters:
Because these ECMs are used in a number of different markets and configurations, the manufacturer uses a process called variant coding to select one table or parameter used in a particular vehicle from a list of stored parameters.
To determine your particular configuration, we are providing the following scanner parameters (these are permanent and you only need to log and take note of them once per vehicle):
The Vehicle Configuration Select is used for several different purposes. Below is an example of a few tables that use this selector:
Note that since the scanner indicates a value of 4 for the Vehicle Configuration Select, the tables labelled as "Var 4" should be used.
Table 18196 is a special case because it actually uses two selectors - the Idle Table Select and the Vehicle Configuration Select. Since the Idle Table Select shows 0, the correct table to edit is Target Idle Speed Selective, Var 0, and since the Vehicle Configuration Select shows 4, the cell in the column labelled 4 is used.
Other table sets that use the Vehicle Configuration Select: 11216-11228 (Max Aircharge WOT), 11242-11254 (Max Desired Throttle).
Table sets that use the EGT Table Select: 14370-14383 (Est Manifold Temperature).
Table sets that use the Pedal Table Select: 13190-13194 (Pedal Characteristic).
Table sets that use the Mass Air Table Select: 51901-51904 (MAF calibration curves).
Table sets that use the Catalyst Table Select: 11316-11319 (Voltage Bank tables).
Table sets that use the Idle Table Select: 18196-18201 (Idle Speed (Gear), Idle Speed (Neutral).
Table sets that use the Lambda Table Select: 12451 & 12452 (Desired Lambda After Start).
Table that uses the Speed Limit Select: 11311 (Speed Limit vs. Variant).
If you are tuning remotely and do not have scanner access to the vehicle, an option would be to modify all of the table copies.
Fuel adjustment tips:
Most of the fuelling at higher loads is done through the Component Protection assembly found under the Engine -> Fuel -> COT, Lean Cruise tab.
The Lambda Full Load (11309) scalar and Base Lambda (11302) table are of particular interest because these allow for fuel adjustments at higher loads including full throttle. Base Lambda's lookup value - Delta Temperature - can be monitored in the scanner and it is computed through adding delta temperature values from a few modifier tables which include one based on ignition efficiency (measured through distance of current ignition angle from optimum ignition angle), engine temperature, etc. Any adjustments made to this table should also fall under the range controlled by the Lambda Rich Limit (12476) and Lambda Lean Limit (12477) tables available under the Fuel -> General tab. Please note that the last two tables do not exist in some early operating systems.
The three model EGT thresholds located in the same tab to enable Component Protection control can be lowered if control is desired sooner (on a forced induction application, for example).
Adjustments for different injectors can be accomplished via the Inj Pulse Mult (12327) table located in the Fuel -> General tab.
Understanding spark timing:
There are 4 main spark tables and 4 optimum spark tables available. In addition, there are a number of tables that act as modifiers to final spark.
For this example, I am logging the following parameters: Spark (SAE), Intake Cam Mix Factor, Exhaust Cam Mix Factor, Knock Prevention Spark Adjustment, Load and Knock Retard:
Below are the contents of the relevant spark tables used while recording this log:
The Intake Cam and Exhaust Cam Mix factor allows us to determine the spark table used currently. In this case, it is table 12687 - Main Spark - Intake Max, Exhaust Min because the Intake reads 99.6% and Exhaust reads 0% in the log.
The log snapshot was taken at 4761 RPM, which at 100% load, corresponds to a value of 21 degrees (Main Spark).
My calibration has the "Use Spark Offset" switch enabled, and the Catalyst Heating Spark Offset (18190) table is being used. We therefore subtract 4.50 degrees from our main table and the resulting spark is 16.50 degrees.
My log also shows that that the car has been detecting knock (Prevention Spark Adjustment - Yes) and as a result, the Knock Offset table is also used to offset the final spark. Subtracting the 3.75 degrees from this table form 16.50 yields the 12.7 degrees of spark shown in the log.
Knock Retard
Just as with any other application, if there is any actual knock retard logged, the final spark will also be offset by the degrees of spark retard.
In addition, if low octane or poor quality gas is detected, the ECM can further reduce the spark timing through the use of one of the Offset, Knock Intensity tables.
You can log the Knock Intensity Level parameter in the scanner to determine if these tables are used. If the level is shown as 1, 2 or 3, the appropriate table above is used to offset final spark.
Tips related to engine torque management:
Engine torque reduction is achieved primarily through spark cut on these vehicles. There are various reasons why the engine control module might decide to reduce torque, including: delivered torque exceeds expected, component protection due to overheating, requests from other modules such as the transmission control module.
In the screenshot below, the Indicated Torque channel exceeds the Maximum Permissible Torque percentage and as a result, the Torque Limiting Active channel shows "Yes."
This is a good indication that the torque model tables need some adjustments.
In our experience with a supercharged vehicle, torque intervention due to perceived EGT rise has been an issue. In the Engine -> Exhaust -> EGT Control tab, there are Temperature Estimation Model tables that can be adjusted to prevent the model EGT from rising too quickly thus resulting in a torque reduction condition.
EGT protection control can be enabled or disabled via the two switches available in the same tab, if desired.
Finally, there is a master switch (12910 - Spark Retard Allowed for TqMgm) which controls the ECM's ability of using spark as means of torque reduction (for any reason). Note that channels such as Spark Intervention Active and Torque Limiting Active will still display "Yes," when the ECM is trying to reduce timing and this switch is disabled.