Catless X-Pipe Misfire/Torque Dip/Bog [SOLVED?]

[V8Juice]

This makes me happy, now I dont have to swap out coil packs hoping it addresses the issue like my mechanic recommended.

[tdott]

Originally Posted by strokemycocktus

I'm all for it. Maybe we could create a separate thread where we would gather everyone with this issue and Alpine tune and then contact Alex. I think it would be fair to pay extra for this feature, so it would be good to split the cost.
I would be so much happier with a smooth low end rev range haha

Created a new thread, please express your interest here:
https://www.m3post.com/forums/showth...5#post26828655

[pdxbimmertech]

Looking for an update and hoping the Epic tune is actually the fix for this bogging issue now that you've been running it for a few days? I've been struggling with this exact issue on my car for quite some time. Running the BW single resonated X pipe with Eisenmann Race rear section on the Dinan stage 2 tune. Same exact issue as others have reported here and elsewhere.

[MikeYQM]

Originally Posted by pdxbimmertech

Looking for an update and hoping the Epic tune is actually the fix for this bogging issue now that you've been running it for a few days? I've been struggling with this exact issue on my car for quite some time. Running the BW single resonated X pipe with Eisenmann Race rear section on the Dinan stage 2 tune. Same exact issue as others have reported here and elsewhere.

It's been about 300km. Still going strong.

[dmlf]

Originally Posted by MikeYQM

So I installed the Epic tune this morning and....

The Epic tune WORKED!

Full disclosure: I bought the tune from Bimmerworld and while I did receive a small but respectful military discount, I did not receive any special discounts. , guarantees or considerations for the work I've done to address this issue.

I installed the tune this morning, before my drive to work.

My observations after about 50km:

The car seemed to start quicker when cold.

Low end torque was immediately noticeable. Obviously the car isn't a torque monster, but the car feels much more connected to the accelerator pedal.

I tried a dozen or so times to replicate the problem, rolling in throttle anywhere from 1500-2500 rpm. I could NOT reproduce the hesitation. If you've had the hesitation, you know it's easy to reproduce. Even in D2, downshifts in the problem RPM band seen a bit earlier and more responsive. There is still a slight rasp/resonance between 2500-3000 rpm that lasts 0.5-1 second under moderate acceleration; I wasn't sure if it was tied to the hesitation or not. It's not.

Overall, the car feels much more cohesive. It runs clean and smooth and feels like factory. Even without the problem hesitation, the car slowly began to feel "cobbled together" and I didn't even notice until driving it with the Epic tune this morning.

Some notes on the Epic Tune:
- You have to send Randy your calibrations file from your ECU and he makes adjustments to that and returns a file to you. Took 4-5 hours for me to receive the file.

- In order to be able to read my ECU, I had to flash back to stock first. I did NOT delete adaptations.

- You also send Randy your mods list and he makes adjustments for that. He also recommends sending near future mods.

- Randy uses your cars calibration data and mods list to develop a specific tune for your car. This isn't a canned tune.

- You get only get 2 revisions. Which makes sense when you consider the points above.

Overall, I couldn't be happier. I'm very picky, and I DO NOT lend my seal of approval unless I truly believe it to be true.

So this a tune issue after all.
Damn, USD 700 for a tune which make throw ~USD 2500 in coils and injector + all the wasted time and effort testing parts, I have to say it's a really hard pill to swallow...

I hope that we will be able to get a tune update soon, move on with this issue and enjoy our cars

[Scharbag]

Originally Posted by dmlf

So this a tune issue after all.
Damn, USD 700 for a tune which make throw ~USD 2500 in coils and injector + all the wasted time and effort testing parts, I have to say it's a really hard pill to swallow...

I hope that we will be able to get a tune update soon, move on with this issue and enjoy our cars

Lol. You ain't kidding. I did not change coils, but I did change plugs, injectors, fuel pressure regulator, O2 sensors, spent time on the dyno, flashed software a lot and changed the way I drove the car (kept the revs up at all times).

Great to see some response though and I hope this gets figured out.

Cheers,

[Shaan]

This thread makes me feel a lot better. Ive been having this problem as well and have been looking for a tune to fix it. ill reach out to Epic/Randy soon

[//steve\\]

Epic (Randy) is the real deal, a true tuner. Like most things in life you get what you pay for. He had one of the most expensive tunes but I'm also not sure I've ever seen a complaint or issues from someone running it. Some of the others.....well this thread is proof.

Also, why are people flooring the car from 2000-2500rpm? I find that to be a situation I'm almost never in.

Wouldn't be surprised if a lot of the people also run the car with the Power mode enabled, which if you ask me is the absolute most annoying way to drive the car.

[V8Juice]

Originally Posted by //steve\\

Epic (Randy) is the real deal, a true tuner. Like most things in life you get what you pay for. He had one of the most expensive tunes but I'm also not sure I've ever seen a complaint or issues from someone running it. Some of the others.....well this thread is proof.

Also, why are people flooring the car from 2000-2500rpm? I find that to be a situation I'm almost never in.

Wouldn't be surprised if a lot of the people also run the car with the Power mode enabled, which if you ask me is the absolute most annoying way to drive the car.

Curious to know why you think it is annoying to run the car with power mode enabled?

As for flooring it from 2000-2500rpm, I may be driving in normal auto mode cruising along and may have to floor it to merge hence why I run into that issue. FWIW

[V8Juice]

Originally Posted by Scharbag

Lol. You ain't kidding. I did not change coils, but I did change plugs, injectors, fuel pressure regulator, O2 sensors, spent time on the dyno, flashed software a lot and changed the way I drove the car (kept the revs up at all times).

Great to see some response though and I hope this gets figured out.

Cheers,

I'm really glad I held off before doing coils. I knew in my gut it wasn't that.

[Spoff_E90_M3]

Originally Posted by //steve\\

Epic (Randy) is the real deal, a true tuner. Like most things in life you get what you pay for. He had one of the most expensive tunes but I'm also not sure I've ever seen a complaint or issues from someone running it. Some of the others.....well this thread is proof.

Also, why are people flooring the car from 2000-2500rpm? I find that to be a situation I'm almost never in.

Wouldn't be surprised if a lot of the people also run the car with the Power mode enabled, which if you ask me is the absolute most annoying way to drive the car.

The bogging occurs with any increase in throttle if in the 2k RPM range. Never have to come close to flooring it. Just need to give it a little more gas and the car response lags and you may need it to go and it doesn’t. Could be a little unsafe depending on the situation.

[//steve\\]

Originally Posted by V8Juice

Curious to know why you think it is annoying to run the car with power mode enabled?

As for flooring it from 2000-2500rpm, I may be driving in normal auto mode cruising along and may have to floor it to merge hence why I run into that issue. FWIW

The throttle is like a light switch with power mode enabled. It's completely on or off. Having it off allows for far greater modulation of the throttle. The car feels a bit slow at first when it's off but after a few days it becomes completely normal feeling.

[tdott]

Originally Posted by //steve\\

Also, why are people flooring the car from 2000-2500rpm? I find that to be a situation I'm almost never in.

The issue is most apparent for me when launching the car at an autox event. Look at this video, you can hear it as the car stops accelerating for a split second.

[pdxbimmertech]

Originally Posted by MikeYQM

It's been about 300km. Still going strong.

Glad to hear this fixed it for you and hoping the tuners out there can make adjustments for people with these forward biased x-pipe style midpipes to resolve this.

I decided to make my own stainless midpipe using the factory resonators and X section along with the factory flanges that connect to the headers. Cost me around $225 for the pipes/bends/O2 bungs and I went this route since I'm already running the Dinan catless file and the DCT software and it was cheaper to see if this option actually resolved my running issue.

I'm happy to report that moving the X back to the stock location did in fact resolve my bogging/hesitation issue I was having exactly as described in this thread. Just wanted to add my "fix" to the thread so others who are handy with fabbing exhaust and already have a tune have another option available to fix this.

[MikeYQM]

Epic tune is -25% at Bimmerworld for BF.

[Ccambrid]

Guys, how did we only get to this answer so late in the thread? I feel like ECU tunes are essential for E9x FBO parts.

My car felt broken after I added test pipes, but an ECU tune crisped everything up beautifully.

[Shaan]

just pulled the trigger on an Epic tune, hope this works

[DBE]

To those in this thread who have experienced the issue

Have you ever noticed the miss repeating itself as the engine climbs through the rev range?

Eg I was testing for a failed coil. Floored it in 6th at 2000 rpm and noticed a clear miss at approximately 2250, 2750, 3500, 4250, 5250, 6500 rpm