Wastegate Rattle - N54Tech.com

ferocity02 · **Wastegate Rattle -** 06-18-2014, 04:25 PM

I installed a JB4 G5 ISO on my otherwise stock 07 335i, this thing is sweet!

But now the wastegates seem to rattle much more than before (the rattling is not coming from the exhaust flap). It is more prevalent at zero throttle low rpm, like coming to a stop. More noticeable when cold. I see that menu 10 and 12 could be used to reduce some of the rattle.

Menu 10: DWP. Adjustment used to mask off throttle wastegate rattle or reduce low throttle lag, Value is multiplied by 2.

Menu 12: Base duty cycle, Adjustment used to mask low throttle rattle and/or alter low throttle boost behavior.

First question is, how do these settings work? What do they do? How are they different from each other? (they sound very similar)

And secondly, how should I change these values to better mask the rattle? What would stock settings be?

Thanks

zach1328 · 06-19-2014, 06:57 AM

Did you already pass the 82k mile mark? I'm sure you're aware that BMW warrants the rattling waste-gate issues for 8 years and 82,000 miles.

If you're not past 82k miles I would try the local BMW dealerships to see if they will replace your turbos. I was hoping to get the rattle before 82k miles so I can get new turbos, but I'm at 77k right now and no signs of a rattling waste-gate yet.

ferocity02 · 06-19-2014, 07:04 AM

Quote:

Originally Posted by zach1328

Did you already pass the 82k mile mark? I'm sure you're aware that BMW warrants the rattling waste-gate issues for 8 years and 82,000 miles.

If you're not past 82k miles I would try the local BMW dealerships to see if they will replace your turbos. I was hoping to get the rattle before 82k miles so I can get new turbos, but I'm at 77k right now and no signs of a rattling waste-gate yet.

I am at 79k.

So without the JB4 the wastegates did rattle, but only barely on cold start. I doubt it was enough to warrant changing the turbos. With the JB4, they rattle much more, so much that the dealer might do something about it. But, if I take it in for dealer work I would have to remove the JB4 first and then the rattle would go away.

zach1328 · 06-19-2014, 08:04 AM

Quote:

Originally Posted by ferocity02

I am at 79k.

So without the JB4 the wastegates did rattle, but only barely on cold start. I doubt it was enough to warrant changing the turbos. With the JB4, they rattle much more, so much that the dealer might do something about it. But, if I take it in for dealer work I would have to remove the JB4 first and then the rattle would go away.

Hmm that's a tough one! You can always try going to the dealer with the JB4, but if they see you have a JB4 tune they may deny the service and put it into their information systems.
If thats the case it will certainly void the extended warranty on the waste-gates and all dealerships will see that information in their system. Some mechanics won't mention your mods and will fix the issue anyways, but most will probably note your mods and void the warranty.

I would recommend taking the tune off and see if they will notice the rattle and replace the tubos. You may have to try a few local BMW dealerships if you get denied. If they all deny the rattle and replacement, then throw the JB4 back on and try again at 81k miles. If they notice the tune then it can't hurt as you'll already be losing the extended warranty in 1k miles from then.
Although if you're caught that could possibly void the HPFP extended warranty too.

GtiGyver · 06-26-2014, 08:18 AM

bump

i too would like to know how these two parameters function and how they are different from each other.

Spxxx · 06-26-2014, 05:38 PM

10 = DWP = default wastegate position
- this is where the WG sits at 0% open throttle
- settings range from 0-100% (0-5 on tach)
- 0 = wide open , 5= almost closed? I think
- 0 = wastegate further from closing and less chance of rattling but longer time to close and more lag.
- 5 = WG almost closed = better throttle response = more likely to rattle (but all cars vary)

Spxxx · 06-26-2014, 05:41 PM

12 = partial throttle WG position
- settings range from 2-4 (around there)
- can be no more than 2 times your DWP setting
- lower value = WG forced further open at partial throttle = less rattle (usually)
- higher value = WG closer to being closed at partial throttle = more rattle & better throttle response
- too high of a value = chances of surging boost and (3.2 is nice for throttle response but often creates rattle)

Spxxx · 06-26-2014, 05:42 PM

someone please correct me if I'm wrong

GtiGyver · 06-26-2014, 08:31 PM

Quote:

Originally Posted by Spxxx

10 = DWP = default wastegate position
- this is where the WG sits at 0% open throttle
- settings range from 0-100% (0-5 on tach)
- 0 = wide open , 5= almost closed? I think
- 0 = wastegate further from closing and less chance of rattling but longer time to close and more lag.
- 5 = WG almost closed = better throttle response = more likely to rattle (but all cars vary)

Thanks Spxxx, that follows my observations, at least for DWP.
I'll have to do some more testing but it makes sense.

ferocity02 · 06-26-2014, 08:38 PM

So what would be considered stock settings?

Do the wastegate settings revert to stock on Map 0?

GtiGyver · 06-27-2014, 08:41 PM

Quote:

Originally Posted by ferocity02

So what would be considered stock settings?

Do the wastegate settings revert to stock on Map 0?

Not sure how to answer your first question, but "yes" to the second.

Spxxx · 06-30-2014, 12:53 PM

Quote:

Originally Posted by GtiGyver

Not sure how to answer your first question, but "yes" to the second.

From what I've heard, the stock (BMW) equivalent setting for DWP is somewhere between 1 & 2.5...

Vorsprung_CJB · 06-30-2014, 04:48 PM

On Map 0 you are still getting ISO boost control, just stock boost targets, so you would still get rattle.

It is tough to say there are equivalent settings for menu 10 and 12 because the stock program adjusts the setting in different situations to mask the rattle, which can lead to undesirable boost response. That is why ISO is more consistent, because it always uses the same setting, but can make rattle more obvious.

What settings cause what rattle depends on your car and WG condition/tightness. Also, since there are two WGs, a setting may quiet one but bother the other. You just need to find the right compromise you can live with. Or get an N55

ferocity02 · 06-30-2014, 08:44 PM

I've played with both settings (menus 10 and 12) and was not able to get the rattle any better (or worse). These settings didn't seem to any difference. With it set to Map 0 the rattle is still there.

Without the JB4 installed at all there is almost no rattle at all. With it installed the rattle is embarrassing and to the point where people ask me if there is something wrong with my engine, even on Map 0.

chi335xi · 07-01-2014, 09:32 AM

Quote:

Originally Posted by zach1328

Hmm that's a tough one! You can always try going to the dealer with the JB4, but if they see you have a JB4 tune they may deny the service and put it into their information systems.
If thats the case it will certainly void the extended warranty on the waste-gates and all dealerships will see that information in their system. Some mechanics won't mention your mods and will fix the issue anyways, but most will probably note your mods and void the warranty.

I would recommend taking the tune off and see if they will notice the rattle and replace the tubos. You may have to try a few local BMW dealerships if you get denied. If they all deny the rattle and replacement, then throw the JB4 back on and try again at 81k miles. If they notice the tune then it can't hurt as you'll already be losing the extended warranty in 1k miles from then.
Although if you're caught that could possibly void the HPFP extended warranty too.

A rattle alone will not necessarily result in new turbos, especially without consistent 30FF codes. My warranty claim was denied because BMW claimed the issue was with the wastegates, and not with the turbos themselves, a position I feared they would take. The turbos hold boost just fine, and the rattle was not considered to be a failure of the turbos. Definitely put your car as much back to stock as you can if you decide to dealer it. In my case, the inspection was pretty intrusive (dealer had my car for over a week), which included looking at the ***.

I'm also only at about 65k miles, so your story could have a happier ending.

Spxxx · 07-01-2014, 03:30 PM

When adjusting settings, you need to leave the settings menu to apply the settings.

ferocity02 · 07-07-2014, 11:31 AM

Quote:

Originally Posted by Vorsprung_CJB

On Map 0 you are still getting ISO boost control, just stock boost targets, so you would still get rattle.

It is tough to say there are equivalent settings for menu 10 and 12 because the stock program adjusts the setting in different situations to mask the rattle, which can lead to undesirable boost response. That is why ISO is more consistent, because it always uses the same setting, but can make rattle more obvious.

What settings cause what rattle depends on your car and WG condition/tightness. Also, since there are two WGs, a setting may quiet one but bother the other. You just need to find the right compromise you can live with. Or get an N55

So the ISO (whatever that is exactly) does not allow the wastegates to retain stock operation in Map 0? The rattling seems to have gotten progressively worse since I installed the JB4.

The rattling comes and goes almost like an on/off switch. If I am slowing down with zero throttle the rattling stops (or gets MUCH quieter) as soon as it hits ~1100 RPM. The ratting at non-zero throttle is minimal but noticeable.

What are the default settings for Menus 10 and 12?

tofu · 07-07-2014, 03:36 PM

Have you checked for a vac leak?

suspenceful · 07-07-2014, 04:10 PM

I have wastegate rattle pretty bad.

Default settings are:
Menu 10 - 4K RPMs
Menu 12 - 2.8K RPMs

I can get rid of my rattle by changing menu 10 to 1K RPMs.

I no longer care about it. I'd rather have performance. Does anyone know if running menu 10 maxed out at 5K or 100 is bad?

hkninja · 07-08-2014, 03:15 PM

Quote:

Originally Posted by suspenceful

I have wastegate rattle pretty bad.

Default settings are:
Menu 10 - 4K RPMs
Menu 12 - 2.8K RPMs

I can get rid of my rattle by changing menu 10 to 1K RPMs.

I no longer care about it. I'd rather have performance. Does anyone know if running menu 10 maxed out at 5K or 100 is bad?

From what I heard if you set it at 100 the turbo is working harder since the default position is closed but you build boost a lot faster.

ferocity02 · 07-08-2014, 03:44 PM

Apparently I was setting mine incorrectly... I tried again this morning and was able to reduce the rattle quite a bit with Menu 10 set below 2 on the tach.

suprchrgd · 02-12-2015, 07:04 PM

Quote:

Originally Posted by hkninja

From what I heard if you set it at 100 the turbo is working harder since the default position is closed but you build boost a lot faster.

Would 4800 (98%) closed be a safe number without causing any damage? i have zero wg rattle at any set point, so im just looking for the best wg position for throttle response.