Hi, I think I need to share my experience with Emotion Tuning device from Celtic.
Disclaimer: I own a 64-plate Z4 20i with the N20 engine, 35k miles, bought it last year. The car hasn't had any problems at all so far, MOT without advisories, service at the dealer and so on. I checked it couple of times with Carly and no errors / faults were present.
When I purchased the device and Stage 1 + Stage 3 remap I thought it would be an easy plug'n'play type of thing, as in their videos. I thought I would use Stage 1 in day to day driving and would temporarily change it to Stage 3 if I'm on a track (can't use Stage 3 day to day because of the insurance company which won't cover more than 25% increase, so Stage 3 will be for track days only which are covered by separate insurance anyways).
The first thing I was asked to do was to connect the device into the OBD port and read the original ECU file. It was quite straightforward apart from the fact that I had to find a Windows PC somewhere (their software won't run on Mac). Fortunately found an old laptop with Windows, installed their app which I downloaded from their website and plugged the device into the laptop. It read the original file, asked to save it to the hard drive (which I did) and upload it back to Celtic to do their magic.
As they say it takes around 4-5 days to get back with the modified file, in my case it was less than that, I got a message that my file was processed and the updated ECU map was ready to be downloaded. I did, uploaded this file back to the device and attempted to write it back into my ECU. Couldn't do it from the first attempt - "Error communicating with the OBD port". Apparently the ignition on Z4 is two-step, first the car turns on when you put the key into the slot and then you also can briefly press the start button while not holding the foot on the brake and it actually turns the ignition on (fuel gauge now shows the amount of fuel), and the device only could write when the ignition is "actually on". Didn't know that, I always kept the foot on the brake pedal when pressed the start button and it actually started the engine. Once I asked the support in Celtic and they explained me that, I finally managed to write the modified map into the ECU.
That's when the things went south. When the device told me that the process finished successfully, the car automatically turned back on (during the process it turned off for some time - screen down, radio off, etc - I was prepared for it as it was described in the manual) and the dashboard was full of warning lights. Brake failure, ESP failure, "check engine" etc. The screen showed the notice that the car has a fault in drive, acceleration is reduced and I need to be checked at the nearest dealer. The Emotion tuning device found an error code (P375C) and asked me if I want to delete it. I thought it might help with the warning lights and agreed, but it didn't help. I checked the car with Carly and it found 37 error codes. I asked the support if it's alright and they said it's not and that I should try write the original file back. I tried but the car started to turn itself off 10-20 sec after I turn the ignition on, and then showed a battery warning light.
The support suggested that I take the car for a 20 min drive to recharge the battery, and try writing the original file again while having a battery charger connected to the car to make sure it doesn't turn off during the process. I ordered a battery charger on Amazon and today tried once again to write the original file back to ECU with the battery charger connected.
It seemed to work, at least the device told me that the process successfully finished. But once the car went back on, the same warning lights appeared on the dashboard.
Right now I am not sure what to do, I asked the support whether I could have the car checked by a specialist, let's see what they say.
So if you're thinking to do the same, better wait until this situation is resolved somehow. For now I just spent almost 500 quid and got no value, only headache.


Disclaimer: I own a 64-plate Z4 20i with the N20 engine, 35k miles, bought it last year. The car hasn't had any problems at all so far, MOT without advisories, service at the dealer and so on. I checked it couple of times with Carly and no errors / faults were present.
When I purchased the device and Stage 1 + Stage 3 remap I thought it would be an easy plug'n'play type of thing, as in their videos. I thought I would use Stage 1 in day to day driving and would temporarily change it to Stage 3 if I'm on a track (can't use Stage 3 day to day because of the insurance company which won't cover more than 25% increase, so Stage 3 will be for track days only which are covered by separate insurance anyways).
The first thing I was asked to do was to connect the device into the OBD port and read the original ECU file. It was quite straightforward apart from the fact that I had to find a Windows PC somewhere (their software won't run on Mac). Fortunately found an old laptop with Windows, installed their app which I downloaded from their website and plugged the device into the laptop. It read the original file, asked to save it to the hard drive (which I did) and upload it back to Celtic to do their magic.
As they say it takes around 4-5 days to get back with the modified file, in my case it was less than that, I got a message that my file was processed and the updated ECU map was ready to be downloaded. I did, uploaded this file back to the device and attempted to write it back into my ECU. Couldn't do it from the first attempt - "Error communicating with the OBD port". Apparently the ignition on Z4 is two-step, first the car turns on when you put the key into the slot and then you also can briefly press the start button while not holding the foot on the brake and it actually turns the ignition on (fuel gauge now shows the amount of fuel), and the device only could write when the ignition is "actually on". Didn't know that, I always kept the foot on the brake pedal when pressed the start button and it actually started the engine. Once I asked the support in Celtic and they explained me that, I finally managed to write the modified map into the ECU.
That's when the things went south. When the device told me that the process finished successfully, the car automatically turned back on (during the process it turned off for some time - screen down, radio off, etc - I was prepared for it as it was described in the manual) and the dashboard was full of warning lights. Brake failure, ESP failure, "check engine" etc. The screen showed the notice that the car has a fault in drive, acceleration is reduced and I need to be checked at the nearest dealer. The Emotion tuning device found an error code (P375C) and asked me if I want to delete it. I thought it might help with the warning lights and agreed, but it didn't help. I checked the car with Carly and it found 37 error codes. I asked the support if it's alright and they said it's not and that I should try write the original file back. I tried but the car started to turn itself off 10-20 sec after I turn the ignition on, and then showed a battery warning light.
The support suggested that I take the car for a 20 min drive to recharge the battery, and try writing the original file again while having a battery charger connected to the car to make sure it doesn't turn off during the process. I ordered a battery charger on Amazon and today tried once again to write the original file back to ECU with the battery charger connected.
It seemed to work, at least the device told me that the process successfully finished. But once the car went back on, the same warning lights appeared on the dashboard.
Right now I am not sure what to do, I asked the support whether I could have the car checked by a specialist, let's see what they say.
So if you're thinking to do the same, better wait until this situation is resolved somehow. For now I just spent almost 500 quid and got no value, only headache.

