I have a 2018 E300 with a custom ECU tune.

I had the dealer service the car for a recall campaign and when I picked up the car the car in Comfort mode felt very slow (stock).


So I understand that the ECU may have been reprogrammed and the transmission needs to adapt to driving mode etc. I drove the car now for 100+ miles and it still feels like a completely different car. (slower)

I had my wife drive it and she unfortunately confirmed my assumptions by asking me what is wrong with it? It feels broken and slow even in Sport+ (This is compared to what we are used to a custom tuned car.)

Here is my question does anybody know that the latest Service Campaign would reset/delete any ECU tuning?


#1. Campaign performed - 2020110019

Campaign No. : Campaign Desc. : Flash SRS Control Unit EDR Function Software 2020110019 20P5498916 This is to notify you of a Service Campaign launch regarding the SRS control unit EDR function software on 80,922 Model Year (“MY”) 2017- 2018 213, 238 (E-Class) vehicles. Affected VINs will be flagged in VMI as "OPEN" on January 15, 2021. Background Issue Mercedes-Benz AG (“MBAG”), the manufacturer of Mercedes-Benz, has determined that on certain Model Year (“MY”) 2017-2018 E-Class (213, and 238 platform) vehicles, the supplemental restraint system (“SRS”) control unit software does not correspond to the current production specifications. In this case, some event data recorder (“EDR”) data might not be recorded correctly. No other functions of the SRS control unit are affected. What We’re Doing MBUSA will conduct a Service Campaign. An authorized Mercedes-Benz dealer will update the SRS control unit software. Parts Parts are not necessary for this Service Campaign.

Entire link to Campaign.
https://www.startekinfo.com/service/...utside/225005/


#2. Campaign performed - TSB LI00.20-P-066887

Complaint: Service display implausible, shows incorrect interval from the 5th service maintenance - Service interval - XXXXX km for vehicles with ASSYST in PTCU (CEPC, CPC_NG) Cause: Inaccurate data record of maintenance interval display (WIA) Remedy: Situation corrected with an AddOn 7982 for Xentry update 07/17. Always install all AddOns before carrying out any updates. Perform N127 update under following path: Powertrain control unit (PTCU) / Special procedures / ASSYST / Check maintenance data for plausibility -

Entire link to Campaign.
https://www.tsbsearch.com/Mercedes-B...00-20-P-066887

 

The tuner may know. It depends on what systems they touched and then which of those the MB campaigns reprogrammed. One thing for sure - don't go in and complain to the dealer. If they check and pass the data to MB you may end up without a powertrain warranty.