Hello guys,

I started learning Motronic tuning couple of months back when i bought from a donor 20th anni an ME7.5 ECU/Complete engine and interior Loom/WBo2 sensor/MAP sensor/Crank sensor/Throttle Pedal/ABS(complete) and few other stuffs; to replace the old ones on my MK4 AGU ME3.8.3 1999 Golf.

 I've been told when i bought my car that it is stage 3 tuned (uncertain of this info) and injectors were from a TT225(380sh cc) but it had the following:
* Decat and 2.5" exhaust with 3" downpipe and APR exhaust manifold.
* Cold air intake with 3" pipe to T3/T4 turbonetics turbo.
* VR6 MAF sensor.
* Ligtweight pulleys from ECS.
* Bosch injectors I presume since the pn is wiped out and inability to identify it.
* SAI/N80/N294 were deleted.
* N75 was only electrically connected, MBC only is controlling the boost.

The car started ok with no misfires, no knocks, but here's where I have difficulties:

1- Idle is erratic/bouncy could it be MAF sensor? I replaced the existing with S4's and copied MLHFM from an M-box ECU bin, set KFKHFM to 1 across all the map but same issue
2- Pig rich running: innovate WBO2 gauge shows AFR around 11 no matter how much i lower KRKTE (slightly lowered each time until .065 ish).
3- Backfire on overrun- normal since it is running rich?
4- I managed to delete via ESKONF the N80/N249/SAI but I still get on VCDS: EVAP Leak detected
5- Always getting on VCDS also: 17705 Pressure Drop between turbo and throttle valve P1297 (I have an HKS dump valve to atmosphere) and
6- also on VCDS: 16618 Boost Pressure Regulation - Limit exceeded (Via logging on ME7Logger I get >2.5 bar boost but my gauge shows only 1 bar boost??
 
I know it is a lot of questions, I would like to know the right way to properly tune it, I've read the wiki here and the S4's, what am I missing? I know there might be a lot, please be gentle

Many thanks in advance

So many hardware issues and no logs.

You don't know what injectors you are tuning for.  KRKTE is not a guess, it's a calculation.

You're not running an N75, how are you controlling boost with the ECU?

Why are you running a dump valve?  This isn't a Poobaru.

Gauge pressure isn't atmos + boost, whereas the MAP sensor is.

17705 is a software issue, if you Google it you'll see.

Thanks everyone. The car now runs smoothly. All is stock except injectors. I think my  gauge is faulty cos the me7logger shows am on 1 afr. Will post back any updates.

Good thing you provided logs