Audi rs3 daza acceleration hickups

[Temoria]

Hello people.
I have a problem with my Audi rs3 2018 that i cant figgure out..

After I picked up my rebuilt engine from my local shop in April inhave had this wierd rpm hickups when Igoing wot or press the pedal down futher than 50% ”approx”

I can see in the log that the rpm isnt going straight up, its going up and down. Just slitghtly, like 100 rpm or so.
U can see on the dash that the needle does very small jumps/hickups as its climbing to reach my full boost which is at approx 4500 rpm. Then when power hits, u cant feel the hickups no more. It feels like a missfire almost but the log does not show anything more than that the rpm isnt steady.
My tuner dont know what it is eather..

We have tried many different thing to find the issue.

-we removed the propshaft to see if it was the reardiff that was bad. SAME PROB
-we changed the transfercase and oil. SAME PROB
-we tried another tune from another guy for my setup. SAME PROB
-we tried changing from uni s4 to s3 and another tune, even stock tune. SAME PROB
-we removed the gearbox and splitted it to look at bearings and shafts. All good.
- we inspected the clutch and flywheel. All good.

Can anyone please help me find a solution for this, i dont know what to do next..

Build spec:
Daza built block and fullt build and cnc ported head.
Ims850 turbo kit
DCT1200 clutches
Upgraded dual lpfp and fuel lines
5” intake and 4” inlet from iroz
Tuned on DS1 and Unitronic S4/S3 on the TCU.
Full e85 (pump e72…)
Rougly around 850hp on 38psi of boost
Water meth injection
Forge motorsport IC and couplers
VTT engine and dsg catchtanks
Motul 10W60 engine oil

+ alot of extra drivetrain related stuff aswell that is not relevant i guess.

Sorry for long post and hopefully I can find a smart guy or women out here to help me put :)

Take care

/S

[TwistRate]

If you are seeing RPM jumps but not seeing wheel speed or actual speed change that align to the jumps then you have clutch slip happening. You can't raise RPM in gear and not also raise speed without slip.


This was a big problem for a handful of tuners back in 2019. Just search for clutch slip.

[yoffer]

Have you checked logs for high and low pressure specified and actual values when it happens?

[Temoria]

It only happends in the lower register. When boost start to hit u cant feel it.
If it was a clutch slip it would have done that when full power is sent to the clutch plates ?
We did check the clutches and they looked OK. They are used ofc but nothing big.

[Temoria]

It only happends in the lower register. When boost start to hit u cant feel it.
If it was a clutch slip it would have done that when full power is sent to the clutch plates ?
We did check the clutches and they looked OK. They are used ofc but nothing big.