CSL Throttle Hesitation and Air Shutoff Valve Noise

[ATB88]

Installed my turner CSL box last night, flashed Terra's modified CSL binary (0401) and modified the tune with TunerPro to have non-CSL spec cam offsets, and used Martyn's ECUWORX tool to disable the appropriate DTCs and change it to a 6MT tune rather than SMG. I'm using COVID-19's MAP sensor solution (Bosch sensor with stock CSL scaling tapped into brake booster vacuum hose). OEM stock CSL IAT wired in using Turner's relocation harness.

Went for a nice long drive to a county without a curfew, and overall the car felt great. But:

1. I noticed that occasionally, when in first, if I hit the throttle, the car gives a completely limp response for a second, THEN burts forward in acceleration, rather than giving normal instantaneous response. A couple times it was "bucking" in this situation (switching between giving appropriate throttle response and limp throttle response quickly over a few seconds). No error codes to speak of. Car is on stock cams and stock US catted headers. Is this behavior normal for a CSL airbox in my setup? Any way to prevent it?

2. When I first turned the car on after completing the swap I let it run for a while and listened around the engine bay for any problems/leaks. One thing I notice is that the air shutoff valve (the one that sits by the e-box) seemed to be triggering every 30-45 seconds or so, like clockwork, making a loud kind of air whoosh noise. Popped the hood after a long drive an hour later and it was still doing it. The stock box also has what I assume is the same valve but I never ever heard it operate in 2 years of ownership. Does this valve just used a lot more on a CSL setup? Or is this a sign that something weird/wrong is up with my install? Maybe this thing is always supposed to go off and make this noise that often even on a stock airbox, and my old one was maybe just broken or not operating correctly?

[COVID-19]

Is the IAT scaling good?

[Martyn]

The car needs a tune, the stock CSL tune is no good for your setup. On euro cars with catless headers it tends to be too rich in most places and this causes the car to bog, so i'd imagine it's quite a bit worse on a car with US headers.

[ATB88]

Is the IAT scaling good?

Should be? I'm using an OEM CSL IAT sensor (https://www.fcpeuro.com/products/bmw...739510#reviews) and what started as a stock CSL tune whose scaling I didn't modify.

The car needs a tune, the stock CSL tune is no good for your setup. On euro cars with catless headers it tends to be too rich in most places and this causes the car to bog, so i'd imagine it's quite a bit worse on a car with US headers.

Yeah I'll be getting a dyno tune in a month or two once I get some headers installed. But I'd gathered the impression the car should run well on the CSL tune in the meantime as long as I fix the cam offsets, just not as good/fast as if the car had proper CSL cams and exhaust. But yeah if this is just how it is with my current setup then so be it. Just wanted to rule out possible errors in install or other possible lurking issues in the car.

I've been monitoring my LTFTs and indeed my bank 2 fuel trims are going a few percent rich most of the time. Is the richness on the cars with catless euro headers due to the tune being optimized for CSL cams (which would be letting more air in)? Or does the CSL tune just tend to run rich in general even on a properly speced setup?

What of the shutoff valve noise I keep hearing every 30-45 seconds? Normal?

[terra]

I don't know about the shutoff valve, but I suspect if you limit the low RPM throttle opening to 70% like the stock US software, that would take care of a lot of the hesitation with US headers.

[Arith2]

Does the ICV play any role with the air shut off valve? I'm super curious on this one. Maybe someone can comment on airflow. I know moving cats down significantly increases airflow out of heads. I would think that increasing the amount coming in while leaving the restriction on the other end would cause your issue. It would be awesome to get specs on this stuff.

Want to post a video of the air shut off valve?

[Sprp85]

2. When I first turned the car on after completing the swap I let it run for a while and listened around the engine bay for any problems/leaks. One thing I notice is that the air shutoff valve (the one that sits by the e-box) seemed to be triggering every 30-45 seconds or so, like clockwork, making a loud kind of air whoosh noise. Popped the hood after a long drive an hour later and it was still doing it. The stock box also has what I assume is the same valve but I never ever heard it operate in 2 years of ownership. Does this valve just used a lot more on a CSL setup? Or is this a sign that something weird/wrong is up with my install? Maybe this thing is always supposed to go off and make this noise that often even on a stock airbox, and my old one was maybe just broken or not operating correctly?

Bumping this thread.

I just finished installing the Karb intake and tuning it with HTE's off-the-shelf software.

Haven't driven it as the roads are still salty out here, but I had it idling for a while just to get the oil up to temperature before shutting it off.

I've noticed the similar "wooshing" noise from the shut-off valve. On a similar cadence.

Have you found out what's causing the noise?

Thanks!