Experts Help - CSL Airbox - Violent Jerkiness and Bucking Under 2k RPM Under Load

[e36addict]

Made an account here just to post. I'm having the same issues with my 2001 M Coupe after a Kassel CSL DME conversion with the Turner airbox. So apparently I just need a dyno tune? I'm over here thinking all the worst lol. Where is this HTE place you guys speak of?

[Cubieman]

Made an account here just to post. I'm having the same issues with my 2001 M Coupe after a Kassel CSL DME conversion with the Turner airbox. So apparently I just need a dyno tune? I'm over here thinking all the worst lol. Where is this HTE place you guys speak of?

https://instagram.com/hte_performance_tuning?utm_medium=copy_link

[siamkazi]

Made an account here just to post. I'm having the same issues with my 2001 M Coupe after a Kassel CSL DME conversion with the Turner airbox. So apparently I just need a dyno tune? I'm over here thinking all the worst lol. Where is this HTE place you guys speak of?

https://hteperformance.com/

[BMWahba]

Made an account here just to post. I'm having the same issues with my 2001 M Coupe after a Kassel CSL DME conversion with the Turner airbox. So apparently I just need a dyno tune? I'm over here thinking all the worst lol. Where is this HTE place you guys speak of?

Yup send him a DM on IG and he will get back to you. Pretty crazy how fast he is at communication! I'm sure he will take care of the issue. Out of curiosity what is your exhaust setup?

[e36addict]

Yup send him a DM on IG and he will get back to you. Pretty crazy how fast he is at communication! I'm sure he will take care of the issue. Out of curiosity what is your exhaust setup?

Catless headers with high flow cats and resonators in the midpipe, leading to Dinan mufflers.

[S14]

Made an account here just to post. I'm having the same issues with my 2001 M Coupe after a Kassel CSL DME conversion with the Turner airbox. So apparently I just need a dyno tune? I'm over here thinking all the worst lol. Where is this HTE place you guys speak of?

Interesting, I'm experiencing the same issue with my Kassel CSL converted DME, Turner airbox and catless headers.

[jet_dogg]

Yes you guys both need a real tune.

[Arith2]

The DME isn't expecting a giant gaping hole with a CSL tune, it's at least expecting the flap. It'll rich the car out because the intake is not designed for low rpm operation. It uses all the available air, freaks out for a second, and then fixes itself when the air flows. I noticed the Turner Box is pretty bad under 3k rpm but it has short velocity stacks and no secondary path for air. It freaked me out the first time this happened and then I went "Ah, this is the hesitation I've read about for years." This is a quick fix when you know what you're doing. The load is limited to 60% below 3000 rpm anyways. Not as much to fix in the tables.

[FastMacM3]

Alright gents; update time:

I got lucky and was able to get on the Dyno today. Buddy of mines shop had it wide open and I convinced him to have Hassan and I try to work this out.

We got it on there and immediately saw that it was WAY too rich in the lower RPM range. Hassan believes it has a lot to do with my section 1 pipe and the additional crossover going on there, not in a stock location. On my setup it was just dumping fuel and choking under 2k RPM.

He adjusted the fuel maps and within 2 test runs trying to replicate the issue, it was completely fixed.

So, moral of the story here, get your airbox installed, waste no time and have Hassan at HTE_Performance_Tuning dial your car in. Every car is different and this proved that, no matter what these are finicky especially with the airbox and nothing beats getting it on the dyno. Once you’re there Hassan will work his magic.

Not only is the car incredibly smooth, buck free and no wild Broncos trying to tarnish my CSL airbox experience, I’m putting down 330WHP/266WTQ with an insanely linear power band all the way through redline.

Massive massive thanks to HassanEido for helping me out essentially overnight, helping me troubleshoot the problem and also tune me on the fly to sort this thing out. Hopefully this thread will live on for future people researching this issue and save themself the hassle and at least start by getting a proper tune before delving deeper into the rabbit hole of other issues.

Nice!

Was this on 91oct or 93?

[BMWahba]

Nice!

Was this on 91oct or 93?

93 here in FL

[pnvhome]

Had the same issue on turner intake when use SS section 1 without cat, and made off second O2 sensors via ECUWorx app, Hassan tried to fix that, but I don’t have access to afr sensor in my city, so the only way to fix for me, a back to euro cat section 1, section 2 is SS X pipe, and stock csl tune with edited value of cams to stock m3, now there is no any problems even on 4 gear and 1600rpm with full throttle, but that is not ok for engine

[Tonggi]

dang that intake sounds so good!

[BMWahba]

Had the same issue on turner intake when use SS section 1 without cat, and made off second O2 sensors via ECUWorx app, Hassan tried to fix that, but I don’t have access to afr sensor in my city, so the only way to fix for me, a back to euro cat section 1, section 2 is SS X pipe, and stock csl tune with edited value of cams to stock m3, now there is no any problems even on 4 gear and 1600rpm with full throttle, but that is not ok for engine

Interesting data point! I do believe it had something to do with my section 1 pipe.

[fattycharged]

I was always unsure how people described this as “jerky” in the past, you hit the nail on the head with “bucking bronco” as that is EXACTLY what it is like. Scary movement, feels like it’s trying to rip itself apart.

This is fantastic news. Mine does the same and boy is it terrible to drive that way, especially coming from a dead stop.

Thanks for the update.

[pnvhome]

I made a little video to show what was the problem, without cats, now with cats car works perfectly, no any such problems, on csl intake from turners

https://youtu.be/R9xWLTlaLns