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Installation of KOCH Tuning Box 2.0 TFSI

4233 Views 25 Replies 5 Participants Last post by  ianmc
Somebody requested that I put up pictures of installation, but I'm also hoping that others who have installed this box can confirm that I have put the wiring in the correct places. This is the e-mail I sent to KOCH Tuning right now:

I received the package today, and saw that the pictures on the instructions were not for my 2.0 TFSI. I proceeded to try to find the plugs, and found the only two connectors that fit your description.

Here is my engine bay:
Here is the Tuning Box with connectors:

Here is the placements of the two connectors:
#1 is on the side of the engine (bottom one in the picture) and #2 is at the back down in the engine (top of the picture). This is the wrong place to put it! See further down this thread

Here is where I put connector #1:

Here is where I put connector #2 (4-pin):

Is this correct for my Audi A5 2.0 TFSI?

I tested my car afterwards, and got no errors, and did a little test drive. It was hard to tell if there was any performance increase in the 5 minutes I drove it... I just wanna make sure that I connected it correctly before driving any more.
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I've having problems still getting a wiring loom that fits!

The location of the #2 connector is different than what I was told though!

In the picture located at I understood the #2 connector to be the brown one at the very bottom right of the picture.
I got an answer from Helmut Koch:

This is wrong. The boost pressure connector is located on the driver side near the water tank for the windscreen.

Take away connector two and put I here.
Here is the correct location:

I also saw the brown 4-pin connector, and the connector didn't fit, because one of the corners is wrong...
This the one you are talking about @ianmc? I asked Helmut if we should cut out the portion in the corner so the new plug will fit over the old socket... it's a bit DIY so I want to make sure... makes me think that they either haven't tested it on 2.0 TFSI a5's or that there is a new socket in our models compared to old ones...
Mjepson, that is the exact same problem that I'm having!

Look forward to your response from Helmut
Got an answer from Helmut:

Yes cut it.
Guess we gotta DIY... have to find my rambo knife
I've installed it now, by having to cut out the side of the contact on both female and male connector on the KOCH cable. That was the only way I could fit it over the original plug and into the car's contact. Had to push quite hard to hear it click in.

Now I need to use some tape to cover up the contacts, as there could get water in where I had to cut away.

Had a 20 minute drive and I can now feel the added power. You can feel it kicking in good at around 3500rpm... more like my old diesel kick. 1st gear spins the wheels, so wish I had quattro ;)

Letting the car cool down now, but will test it again a bit later...
Why did you write it to S5 Performance & Mods, there is section A5 Performance & Mods, where this thread should be, I think. :music-smiley-019:
Sorry... i'll blame that on being a little excited :(

Can an admin please move it to correct forum... thank you!
Bad news :(

I was just out driving and this light came on:

This is the light for abgasskontroll (exhaust control?), and the manual says I have to take it in to a workshop ASAP ...

Why has this light come on now? Has the box gone over the limit of something in the engine?

Can I remove the light with VAG COM? I have a cable laying around here from my A3, so I'll try to connect with my laptop and get a reading...
Oh no! :(

Have you simply tried removing the box and turning the car off until it enters sleep mode (after 5 mins) before restarting?

Failing that it really doen't look to be a positive sign for the Koch module!

Feeling your pain mate!
Yes I've removed the box and let it sleep for 30 minutes, but light is still there.

I've talked with Helmut quite a lot past hour on e-mail and he says the following:


The maximum that happens is, that you get a error because the boost level is too high. The MSC usually generates 0.25bar boost increase.

ERASE the error codes and try again, please. Boost error normally do not turn on the check engine lights.

After you have deleted all errors, try again, please. I try to find out what connecter it is where you connected the device first – I hope you didn´t harm the device.
I asked him how I could remove the warning light

Go to the dealer and let them read the fault codes, this is helpful for us in order to get an idea what may happened.
I still think it's a pain that I have to drive around with this light until I can take it into a dealer. They will probably ask questions too. I have a friend with VAG COM though, so I'll try to get him to read and reset the error code.

I now got this reply from Helmut:

!!!!!!!!!NEW ORDER!!!!!!!!!!!!



I told him that I'm fine with him sending a new one, but that I think he should send a completely new one to me, and also pay for the shipping costs for the old unit, seeing what an ordeal I'm going through. Sound fair?
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Very much so

I'm surrently waiting for Sanspeed to come back to me with a new loom - as I am not DIY'ing such a vital component - also don;t want tobe "blamed" for damaging the wiring by the DIY fix

Hope you get it sorted - I'll let you know once I have everything in hand and have chance to fit mine
I wish I had been as patient as you are ;) I'll keep you posted on updates.
I got a friend who has VAG COM today and we were able to reset the warning light in the dashboard and read the following error codes.

2859 - Oxygen (Lambda) Sensor B1 S2: Heating Circuit: Malfunction / Open Circuit
P0036 00 [032]
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 888 km
Date: 2009.05.29
Time: 10:18:43

5671 - Boost Pressure Regulation: Control Range Not Reached
P0299 00 [096]
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 920 km
Date: 2009.05.29
Time: 13:30:39

4025 - Oxygen (Lambda) Sensor B1 S2: No Activity
P0140 00 [237]
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 915 km
Date: 2009.05.29
Time: 13:27:08

I think the first one is related to me fitting the Contact #2 to the wrong place:

The "bad" thing is that I got the third error (4025) again after I had cleared these three errors from the log. The engine was running, and it came up again. It didn't set of any warning lights as it is a priority 2 error, but It would still be good to figure out what this is... anybody have any ideas?
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Whithout being an expert, i can see its the Lamda sensor, so we are talking about emissions...
Well, after driving with the yellow emission light cleared, it came on again yesterday after an hour of driving, so I'll have to take it in to the dealer and ask them to fix it (and play dumb)

I think the "no activity" from the lambda sensor actually means it can't get a reading because I probably fried it... you live and you learn :(
It's quite common for lambda sensor to fail (due to the temperatures they have to endure), so I doubt you will have too much problem in getting the matter rectified
If I understand it right, they sell what they haven't tested properly.

"DO NOT PANIC" is great answer...

As I have read it, I have found another reason why I hate these modules/boxes :cheers:
@c99 - These boxes are certainly bad if you have idiots like me fitting them without proper instructions and a contact plug that doesn't fit where it should ;)

I would remap the ecu, but I don't want to void the warranty completely. Atleast the box is removable and non-detectable after removal.

Also after doing some research, a non-flashing emission light isn't normally a "serious" problem, so there isn't any reason to "PANIC" like I almost did. But I still messed up the o2 sensor, but hopefully that is a quick fix tomorrow by the dealer.
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