Karbonius Airbox Lean Issue After Csl Conversion

[Tigm3]

Hello all wondering if anyone can share some knowledge on a lean AFR 16.9 mixture at operating temperature on idle after a Full carbon Karbonius csl box with snorkel install along with Kassel csl firmware, and Kassel map sensor conversion kit. Will be driving to perform a Alpha-N Tune/Dyno. All installed pipes, fittings, clamps are fastened securely, along with the map sensor kit installed diligently. Engine not running perfectly smooth on idle I have a bimmerworld straight pipe and do hear valvetrain noise out of tailpipe.
Also installed the IAT harness connects to old MAF with sensor.

I do not have access to INPA just a obd2 reader that when scanned shows no faults.

*Just a note before installing Kassel map sensor conversion kit it was giving the same issue of a lean mixture I ordered the Map sensor kit thinking it would rectify the issue however it is the same result.

If anyone in the community can help out I would be much obliged.

[karter16]

I can't say for sure that this is the problem, but I would note that the Kassel tune is just standard CSL software and tune with minimal changes for vanos offsets, etc. A lot of us have found that with standard M3 cams etc. we need quite a lot more fuel at idle than the CSL tune (https://nam3forum.com/forums/forum/s...957#post243957).

Edit: if you want the easy answer from a tune perspective, reach out to Bry5on and get onto his Mullet Tune.

[Tigm3]

karter16 Much obliged. does the Kassel csl map sensor kit even do anything then? I feel it was a waist. A Alpha-N tune is the real resolution. Is it safe to drive until a Alpha-N tune ?

[George Hill]

IIRC someone on the forum (heinzboehmer?) posted some data showing the Kassel MAP sensor location introduced some "noise" in the MAP sensor signal?

On the forum here most people seem to be using the OE mounting location or COVID-19's solution.

[Tigm3]

George Hill in my case I had it before I installed the Kassel map sensor after carbon intake install.

[George Hill]

🤷♂️Its entirely possible two different items can cause the same issue. The diagnostic process would say put the car back to "stock" and diagnose from there.

[Slideways]

How old are the pre-cat oxygen sensors?

[Tigm3]

Slideways I forgot to mention they are genuine csl catless headers.

[Bry5on]

For what it's worth, the MAP sensor absolutely cannot be expected to solve this issue, and I don't believe Kassel touches the MAP sensor part of the tune at all in any case.

Second, yes that Kassel MAP sensor location seems to cause too much noise at very low rpms as it's pulling MAP from just one intake runner. Heinz and I verified this from his datalogs, and he corrected some odd low-rpm behavior by moving his MAP sensor and now operates more in-line with other properly running cars.

Frankly: Kassel MAP < No MAP (~Alpha-N) < Any other MAP kit. I'd disconnect or ditch your Kassel MAP kit in favor of another location to get manifold pressure.

It sounds like you simply are running your non-CSL cams with a CSL cam tune and it's running poorly as a result.

[Tigm3]

Bry5on I agree had I known this before I would not have purchased the kassel map kit. however at this point should I leave it in place until I get a tune? or take it out would driving without it even make a difference?
when I had the stock airbox I did not have any running poorly/noise issues I presume the carbon airbox gave that effect as I did not hook up the map sensor kit to same time as carbon airbox to test things out first. Yes non csl cams. Much obliged for your input.

[Bry5on]

Bry5on I agree had I known this before I would not have purchased the kassel map kit. however at this point should I leave it in place until I get a tune? or take it out would driving without it even make a difference?
when I had the stock airbox I did not have any running poorly/noise issues I presume the carbon airbox gave that effect as I did not hook up the map sensor kit to same time as carbon airbox to test things out first. Yes non csl cams. Much obliged for your input.

The MAP kit you have now won’t make much difference whether you have it plugged in or not. The tune is far off enough that MAP is unlikely to make it noticeably better or worse. If I were in your shoes, I would just unplug the Kassel MAP sensor and run without it until you decide to add it back in in a better location.

You will likely also notice inconsistent rev matches, lumpy/difficult throttle under 3500rpm, really rough cold starts, difficulty holding smooth throttle inputs on uphill starts, and long term fuel trims that are not very close to 1.0. These are all tune related things because you’re set up for the wrong cams. It’s not necessarily the carbon airbox itself, but it’s the software/tune + carbon airbox that’s the trouble.

[Tigm3]

Bry5on understood would there be any risk of engine damage if I drive it ?

[Bry5on]

Bry5on understood would there be any risk of engine damage if I drive it ?

There is no notable difference in risk between having the MAP installed and unplugged.

Many users have gone for years running on this tune file without destroying their engines. Risk of damage is not zero but history would point to risk being pretty low.

[Tigm3]

Bry5on I am very grateful for your clarification and fast response Bry5on you are a great member!