Hey y'all.

To chip or not to chip?

I've owned my 2014 e550 coupe for 18 months, and aside from a couple small electronic failures (front parking sensors alarm at random times for apparently no reason at all, passenger side seat tilt motor fried) I love her.
My favourite thing about this car is the (imo) unparalleled balance between power and safety/comfort features, offered in an elegant and work appropriate shell. However more powerful cars catch my attention often enough and I've tested many, but nothing has convinced me to change yet.

In order to quench my thirst for MORE POWER, I'm considering getting an ECU tune. I know Renntech has great ones, but they are very expensive (2-3k). Does anyone have any experience or recommendations?

My car is otherwise Stock and I have no intention of doing any hardware upgrades for the time being. I can see myself playing with the exhaust in a couple years.

My car is still under Mercedes warranty, so I'm also worried about messing that up. Ideally I would like to get the handheld programmer so that before taking the car in for services, I can bring it back to stock.

 

A couple of us with the TTv8 have gone with the OE Tuning tune. I have been running it for a little while now, and it's great. Pricing is very competitive, and I have brought my car in for service with Mercedes without any issues. I imagine if I had something go wrong and it was due to the tune, maybe they would say something, but...I haven't had any issues yet, haha.

I would suggest the tune. if you have concerns, wait until you are out of warranty, and then get it, and wonder why you didn't get it earlier . Maybe go with the exhaust mod first.

 

Hi Steven,

Good to hear you're enjoying your car as well. As you said, the E550 coupe, in straight stock form, is a great balance between power/performance that also provides solid safety/comfort features needed for a good DD vehicle. A perfect sleeper car.

You also say you want more power, but don't want to risk loss of your warranty should any sort of problem result and MB subsequently discovers your ECU tune down the road and can trace it back to the cause of your problem. Thus you want an OBDII-type tune, so you can switch back and forth between stock and whatever tune you get. This is what I've found so far:

1) Our ECU's can only be tuned via taking them out and mailing them to one of the tuner companies. Not hard to do, but not the OBDII path you want. There appears to be NO handheld OBDII style tune available for our specific model / year cars. So in the event you wanted to switch back to stock before going to MB for service, you would need pull your ECU out again and mail it back to RennTech or whomever you had do the tune. They all will restore it to stock mapping if you ask. It's just NOT what I would call plug and play in the sense of what you or I would be looking for.

2) When you mail your ECU out, the tuner company may need to drill a small hole in the ECU to allow them to remap your ECU. They will of course fill-in and re-paint where they drilled the hole, but if MB looks at your ECU they may discover this "tampering" as MB refers to it, you may or may not lose your warranty. It depends what problem your car has and whether they can trace the ECU mod directly back to either the direct cause or a contributing factor to the problem you have. So if you go forward with an ECU tune, one of your questions should be whether they need to drill this small hole in your ECU cover. Obviously, if they can perform the tune without leaving any outward physical evidence of their work, that would be ideal. Why make it easy for MB to spot your mod, which MB considers illegal tampering.

So that is what I've learned about what is involved in getting an ECU tune done to our cars. Something for you to think about, since it is not exactly what you said you are looking for. The day RennTech comes out with a handheld OBDII tune for our cars, I will buy one. Until then, I'll hold off. I tend to keep my vehicles at least 7 to 10 years, so the idea of having to do this process, with technical support for the tune 1,200 miles away, just isn't attractive.

If I were to go with any of the tuning companies, I too would probably opt for RennTech simply because they seem to have to most experience with MB vehicles specifically, been in the business of tuning MB vehicles the longest of the major tuners that do MB vehicles and I have yet to read about any of their tunes causing major engine or electronic issues afterwards. To me, that is worth the premium they charge in price. What good is saving a few hundred bucks on the ECU tune, if you end up with a series of intermittent CEL issues or have to go down the road of replacing a litany of parts afterwards. You get what you pay for in most cases.

Hope this is of help to you.

 

So is this tune via OBDII port or did you have to FedEx your ECU to OE Tuning?

 

I'm not 100% sure about the 2014 model year but my for my 2016 there is no ODBII port to connect into so the ECU needed to be pulled and sent out for flashing. Removal of the ECU is a simple 10 minute procedure. Hardest part is disconnecting the battery.


Mine is the E400 so I have the 3.0 twin turbo, only drove the car for 3 weeks B4 I got it tuned but damn this car is crazy fast now. I went with OE, at $1200 it was worth every penny.

 

Thanks for verifying how OE does their tune. That's what I thought after reading through their site a while ago. Glad to hear you like their tune. Performs well with no CELs right? Just a question, did you notice before you re-installed your ECU if they had to make that tiny drill hole in the ECU case that they latter had to patch and paint to conceal?

By the way, your car does have an OBDII port, as all late model cars do. MB uses the port for various diagnostic / service purposes. It is just that the tuner companies can't use the OBDII port to reprogram the ECU on these newer cars due to MB encryption software that none of the tuner companies have apparently been able to crack yet.

Thanks again for your reply.

 

As Richard P Harve posted, you have to send the ECU in for our cars (I also have the 2014).

 

Thanks SnakeDoctor. That's what I thought from my research. Good to know that the OE tune doesn't create intermittent problems like I've read with some other tunes. How long have you had the tune in place?

Do you have state vehicle emission inspections in Texas. If so, does your car pass with the tune or do you have to revert the ECU back to stock settings for the state inspection?

 

I bought the tune at the end of 2015 of I recall correctly. I have had an inspection done since then with no issues.

Very happy with the purchase. I believe OE will even reflash your ecu once if mb overwrites it for whatever reason.

 

looking at oe tunes website it seems like buying the "my genius" or the "android flashloader" I will be able to get the maps from them and do the work without mailing in my chip.

"maximum of 4 modified files can be stored on the cloud and the user can flash the original read file from the car or any modified tune as many times as needed"

Seems pretty straight forward!

 

The tune for our cars is listed as "bench flash" meaning you have to mail your ECU to them. Yes OE has a handheld device, but that is for different model cars.