How to tell if ECU is tuned?
 

I just bought 2014 E550 and considering ECU tune (Weistec?). Well, I checked their instructions... They said send us your current ECU, but it has to have stock tuning. So my question is how to tell if I have stock tune? I bought the car from used car dealer, and sure they do not know about it.

I thought easier way and that time consuming.
Why wait before tuning?

you can call each of the big name vendors with your vin and see if its in the database.

Hypothetically, One way to tell is if your car goes above 133MPH. That's the stock speed limiter, and tuners always increase the speed limiter.

We talk about tuning here, but it is not the norm. My guess is that for every ECU-tuned car out there, there are 5,000+ other cars with factory tunes. So you can play the odds. Unless you know the previous owner to be a tuner type, I would assume the car is not tuned.

good assumption

Two ways to find out.

1. See if you can open your ECU. You will have to unscrew 7 screws.
Then, open it. If you cant open it. Mostly likely, its untouched.
ECU typically is sealed by those black colour silicone. See 2nd picture.

Inside the ECU, there are 3 screws need to be taken out. After that, see if you can take off PCB board out of metal plate.
If the PCB board can be taken off the metal plate. Which mean its been taken out for tuning.
But some tuners can access boot pin from top of PCB board.


https://cimg3.ibsrv.net/gimg/www.mbw...29362196fc.jpg

https://cimg9.ibsrv.net/gimg/www.mbw...ec06df457a.jpg




2. See if there is a small drill patched mark in this area.
https://cimg7.ibsrv.net/gimg/www.mbw...82bcfb8cf2.jpg

3. Go Race with stock E550, see if you can out run it.









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