AlpineMSS Low RPM Catless X-Pipe Misfire/Torque Dip/Bog - RESOLVED

[tdott]

Originally Posted by Impastokitsch

.

Im on decat stock Xpipe with straight through on my MPE

This does not apply to you. The stock xpipe will not have a problem.

[Redd]

Originally Posted by Impastokitsch

Am from Singapore

I was on Etuner Map and one of my buddy purchased alpine mss tune from alex 2 weeks back and he was enjoying the bubbles and flame of this map.

With tht, i have also purchased the tune few days back and im waiting for the kit to arrive

I m writing to say my buddy do not have this issues so far but could it be octane98 gas do not face such issues? Anyway Alex is good in customer service; he answer all questions within hours on the same day.

Im on decat stock Xpipe with straight through on my MPE

Cant wait for the tune to happen

Problem only occurs on x-pipe with a very forward located x joint (immediately behind the gearbox) . Other x pipes with stock located joints (near the middle, above the metal bridge/bracket) don't seem to face this issue.

[Impastokitsch]

Originally Posted by Redd

Problem only occurs on x-pipe with a very forward located x joint (immediately behind the gearbox) . Other x pipes with stock located joints (near the middle, above the metal bridge/bracket) don't seem to face this issue.

Just got the package with love from LA

[TechE]

Stage 2 tune, BW resonated x-pipe, OEM rear section, Dinan intake, 92 oct, 6mt.

I don't notice a wild drop in power like some have mentioned, but there does seem to be slight hesitation in that rpm range (rasp more than anything). Let me know if I can be of assistance? Looking forward to positive results!

[tdott]

Originally Posted by E.Usaf

Stage 2 tune, BW resonated x-pipe, OEM rear section, Dinan intake, 92 oct, 6mt.

I don't notice a wild drop in power like some have mentioned, but there does seem to be slight hesitation in that rpm range (rasp more than anything). Let me know if I can be of assistance? Looking forward to positive results!

For me, it's not as noticeable in normal street driving. As you are mostly part throttle there. I don't drive in D mode often so that could be why. Others have mentioned something similar happening in higher gears at lower rpm trying to accelerate.

The issue is most apparent for my 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.

On a DCT car it is when trying to launch the car smoothly. If you just stomp on the pedal the DCT will just raise the RPM and dump the clutch and you'll have a smokey burn out and won't notice this issue.

On a 6MT car I am not sure how to best reproduce this, but you would need to be at WOT at around 1500 rpm, then once over 2k is where it is usually felt.

[dmlf]

Any news from the test group ?

[strokemycocktus]

Originally Posted by dmlf

Any news from the test group ?

I tested it yesterday, there is a big improvement. On part throttle it's almost gone, on full throttle there is still some hesitation but definitely not even close to what was before. The car doesn't choke any more and that weird loud (intake?) rasp is gone too.
I'm not sure if I posted it, but you could cleary hear it at the beginning of this video. I floored it in 1st at low rpm and it choked for a brief second at first - that's the issue everyone is refering to here. This is now gone

[dmlf]

Ahhh ! That's great news. I'd like to be able to test this as soon as I get my car back.

[tdott]

Originally Posted by strokemycocktus

I tested it yesterday, there is a big improvement. On part throttle it's almost gone, on full throttle there is still some hesitation but definitely not even close to what was before.

Did you test the first file or the 2nd revision?
Only did 1 drive on the second file and I am feeling like the first might have been better when launching it.

I need to do a few more drives to tell for sure.

[gh0stE92M3]

Originally Posted by tdott

Did you test the first file or the 2nd revision?
Only did 1 drive on the second file and I am feeling like the first might have been better when launching it.

I need to do a few more drives to tell for sure.

I tried the second file and it has improved partial throttle but wot still hesitates a little bit from 2k-3k then it drives normal. I have a 6mt and if I wot at 2.5k rpm it isn't as noticeable, but from 2k it's still there but not as bad as before. I'm hoping the next file will be better.

[TechE]

I'm going to retract some of and add on to my previous post. It absolutely bogs until 2.5k rpm. Did a 3rd gear roll around 1/2 throttle, and that's all I needed to confirm. Took a video but it probably wouldn't help much. I honestly thought it was just the engine power curve but putting 2 and 2 together makes much more sense now. I'm also about certain the rasp is a byproduct of it.

[dmlf]

Originally Posted by E.Usaf

I'm going to retract some of and add on to my previous post. It absolutely bogs until 2.5k rpm. Did a 3rd gear roll around 1/2 throttle, and that's all I needed to confirm. Took a video but it probably wouldn't help much. I honestly thought it was just the engine power curve but putting 2 and 2 together makes much more sense now. I'm also about certain the rasp is a byproduct of it.

Alex@Alpine is curently working on a solution to this issue, be patient and I'm sure he will be able to provide a solid tune for this.

[gh0stE92M3]

So any updates from people that have gotten on the test file with alpine? Or has this issue died out? Still considering going with epic tune if this doesn't get resolved or just change out the whole system I'm running.

[tdott]

Originally Posted by gh0stE92M3

So any updates from people that have gotten on the test file with alpine? Or has this issue died out? Still considering going with epic tune if this doesn't get resolved or just change out the whole system I'm running.

It's much better, the issue is 90% gone for me. I sent Alex some logs after testing revision #2. It's much more livable now. I just feel a very slight change at that rpm. It's not a hesitation anymore where the car stops accelerating. It's more of a change over like when Vtech kicks in.

[94jedi]

What I'd like to see now is a comparison of the Epic tune vs Alpine tune w/ the BW x-pipe. I'm sure there's not much difference but it would be nice to compare the two.

[fth001]

Originally Posted by tdott

It's much better, the issue is 90% gone for me. I sent Alex some logs after testing revision #2. It's much more livable now. I just feel a very slight change at that rpm. It's not a hesitation anymore where the car stops accelerating. It's more of a change over like when Vtech kicks in.

Agreed, I was able to put my BW pipe back on this weekend and test out the new tune. I would say that it's much better now. I can accelerate hard in 3rd and 4th now and not put my car in limp mode. You can still feel a little hesitation but its gone almost immediately under throttle. Just need to add the burbles back in this tune and I think we're good.

[tdott]

Originally Posted by 94jedi

What I'd like to see now is a comparison of the Epic tune vs Alpine tune w/ the BW x-pipe. I'm sure there's not much difference but it would be nice to compare the two.

How would you compare the two objectively? Usually dynos don't start until after 3k.

[gh0stE92M3]

Originally Posted by tdott

It's much better, the issue is 90% gone for me. I sent Alex some logs after testing revision #2. It's much more livable now. I just feel a very slight change at that rpm. It's not a hesitation anymore where the car stops accelerating. It's more of a change over like when Vtech kicks in.

It's funny when I offered to send Alex logs he said logs aren't gonna fix the issue. Glad it's working better for you. Hope he gets this sorted out.

[Alex@Alpine]

Originally Posted by gh0stE92M3

It's funny when I offered to send Alex logs he said logs aren't gonna fix the issue. Glad it's working better for you. Hope he gets this sorted out.

And logs aren't still going to fix the issue. The vehicle is in a transitional period from part throttle to full throttle. Only back and forth testing is going to fix the issue.

[gh0stE92M3]

Originally Posted by Alex@Alpine

And logs aren't still going to fix the issue. The vehicle is in a transitional period from part throttle to full throttle. Only back and forth testing is going to fix the issue.

I totally agree with you that logs aren't going to fix the issue, but using the logs as a tool to actually see what's going on during that transitional period will help instead of "tell me whats happening". With previous cars I've owned whenever there's an issue with how the car runs my tuner would ask for logs to be able to replicate the issue so he could see what the car is actually doing. I maybe new to the whole bmw dme scene but I've been around cars and building them for some time. Call me old school but logs help to figure out the problem and help you as the tuner to solve the problem. Making a generic tune for a platform is fine, but from my experience every car is different, and every car runs differently. Hence why each issue varies a little.

[Alex@Alpine]

Originally Posted by gh0stE92M3

I totally agree with you that logs aren't going to fix the issue, but using the logs as a tool to actually see what's going on during that transitional period will help instead of "tell me whats happening". With previous cars I've owned whenever there's an issue with how the car runs my tuner would ask for logs to be able to replicate the issue so he could see what the car is actually doing. I maybe new to the whole bmw dme scene but I've been around cars and building them for some time. Call me old school but logs help to figure out the problem and help you as the tuner to solve the problem. Making a generic tune for a platform is fine, but from my experience every car is different, and every car runs differently. Hence why each issue varies a little.

The problem was identified. Going back and forth between logs will not do anything at all period. I am sorry you are unhappy with this answer but this specific problem isn't going to get fixed by multiple logs from the car.

You can ask every single person in the test group, I did not ask any of them for logs. The gentleman above and another gentleman from overseas volunteered their logs without me asking them.

If you still keep in contact with your respected tuner ask if the transition period from part throttle to full throttle can be fixed through multiple logs. Yes, you will see the original problem in the log but at the end of the day only user feedback will tell you if the problem is fixed.

[94jedi]

Originally Posted by tdott

How would you compare the two objectively? Usually dynos don't start until after 3k.

that's a good point. I've not had a car dyno'd in a while. Not sure other than logs but even still, same environment, temps, etc. could wreak havoc.