Audi A4 CPMB K04 Tune Help MED17.1

[Dhogue]

Hello,

First time diving into torque based tuning...

The A4 is a personal car and is a Flex fuel CPMB motor that has a 3" catless exhaust(track car), apr intercooler, glitter from the previous stripper owner and K04 turbo with a higher flowing turbine that has a 14lb wastegate spring https://www.turborebuild.co.uk/enhan...ade-anti-surge .

I think I figured out how to get the 14lb wastegate "close" to being tuned correctly with the TIP adjustment. The Desired vs actual boost is closer and the ECU does not go into limp mode anymore. The throttle seems to be highly choked down and there must be a limiter somewhere as Desired boost tappers off.

I also adjusted the...

Turbo PR table

Optimum torque table

Torque to Load Table

Enriched the Power Enrichment Driver Demand table for more fuel.


The afr's are close but the desired boost tappers off from actual and there is a 40-50 ftlb of torque difference between actual and commanded.


I attached files for anyone that would want to review and doing so would be greatly appreciated. I want to learn what is needed to get the torque and boost matching up so I can then learn/figure out how get the torque /power/boost up. I started filling with e85 for detenation/ tooner protection so the ethenol is 65%

Thanks,

David

[LAGP]

Hi Dhogue, I am tuning an Audi TT with mafless Med 17.1, somehow similar to yours, my problems are with the MAP not being able to read more than 2.5 bar absolute (about 22 psi gauge) I try to upgrade to a 4 bar MAP sensor but the ECU is not able to read properlly, what is your max boost ?

[Dhogue]

Messing with the gain for the wastegate and locking the bypass valve from Opening from pr limits reached I was able to get the boost steady at 16-17psi (external gauge) with no spiking when floored with a gear downshift.

The map sensor limit makes sense as when I converted the actual and desired boost logged values they read 26-28psi.

Current issue now is I found the throttle percentage table and when I request 60-100% throttle blade position at the give airflows it does it but now I'm hitting some other limiter I'm unaware of and the car is cutting spark/chopping throttle body.

[LAGP]

I got some help here in the forums, here is a file with some aditional parameters, maybe this can help you.

[LAGP]

I was looking at your calibration to get an idea on how the ECU adjust for the E content in the fuel, but have not been able to locate the tables, could you share some light on this.

[Dhogue]

Yeah I'm either missing something or the only real adjustments mimick a piggy back fuel controller lol.
Didn't see afr,timing,or flex fuel tables. There are compensation tables but nothing I'm used too.

My understanding is the computer definitely tries not to blow the engine but when messing with boost control and what not this little k04 can build boost in a hurry.....

[LAGP]

I swaped to a 4 bar MAP, which would be the max our ECU can read acording to the range avaliable for [ECM] 3644, but can not get more than 2.5 bar absolute reading. Do you have any sugestions on how to make this work?

[Tommerrr]

Did you calibrate the sensor in the tune? Also these ECUs have a 2550mbar limit.

[LAGP]

Yes I was able to do the calibration for the 4 bar MAP, engine idles and runs ok but have not figure how to go over the 2550 mbar boost

[TWiST]

I had made a request several months ago to get the flex / SF / Secondary Fuels, tables added to a CPMB 8K5907115Q MED17.1 and they have added them. Have not tested yet but it looks legit. I am guessing they should be available for you as well. Just download the newest beta.

[bb-tt]

if you search tjdubbs has posted a basic k04 tune on here formed 17.1