Wastegate rattle after jb4

[Donny_G]

I recently intstalled jb4 (+ dp's,dci, cp and dv's) on my n54 335i. The wastegate rattle is driving me insane. Sounds like a rattle snake in the exhaust!

I'm currently trying all the different waste gate positioning /lag settings on the jb to try and remove it but no luck thus far. Furthermore it seems to be during acceleration.

I have done some research on the various forums and it seems to be a common prob with the jb4 g5 iso boards. I've also seen a few suggestions to adjust the actuator rod.

Does anyone else have this problem on their n54 and did you find a solution?

 

[KrS24]

Alot of people had the problem. Myself included. I moved the default wastegate position to 19 and that seemed reduce the rattle the most. There are options regarding the actuator rods but you will need to remove the turbos.
The best option I have seen is to get a set of forge actuator rods. These are not cheap but will do the trick. Wastegate rattle doesn't mean your turbos are on their way out. I had rattling wastegates for 10 000km on a FBO car.

My suggestion is to use the jb4 to mask the sound when driving in parking lots etc where the sound is amplified. You will get use to the sound. It's part of the N54 charm.

 

[Donny_G]

Thanks bro. Charm?! Its driving me crazy.

I'll try that setting. Any idea where I can get the actuator rods from?

 

[KrS24]

Anybody who stocks forge products should be able to help. Vagcafe springs to mind. Rennzport should also be able to help. They are known for stellar service and support.

 

[bmsportzn135i]

Also, just make sure that the DPs aren't maybe touching something.
The space is tight wih our RHDs, and some times what sounds like wastegate rattle might just be a DP touching something.

 

[Donny_G]

Thanks. The "19" setting seems to make a difference. But its still there. I'll pursue a more permanent solution and update this post.

 

[Acheron]

Replacing the actuators on the turbos with the Forge version (or equivalent) is a waste of time as it is not the actuators themselves that have worn.

99% of the time the rattle is a result of the bearing in the wastegate flap having worn to the degree that there is play while partially open/fully closed resulting in the rattle noise under light acceleration/deceleration boost conditions. This why under wide-open-throttle/higher boost you will not encounter rattle as the wastegate is further away from the exhaust housing.

It's likely that you've had wastegate rattle since before the JB. Adding catless DP's usually amplifies the sound significantly, but the JB's default wastegate position setting can also increase the prominence of the rattle.

When does your rattle occur? Low throttle (parking lot speeds), revving at idle, deceleration, etc? Your best bet here (taking into account my question) is to adjust default wastegate position (menu 10 from the steering controls or in the JB app itself) and the wastegate pulse width (menu 12 from the steering controls) until the noise is either lessened or gone completely. Bear in mind that as your wastegate sees more wear the sound may return.

Alternatively you can get someone who knows their way around the N54 turbos to adjust your existing actuators by tightening the arm a few turns (usually only needed on the rear turbo) forcing the wastegate to be held tighter against the housing. Note that once again this is a temporary fix as increased bearing wear will occur and no amount of further actuator arm tightening will fix the issue.

 

[Donny_G]

Yeah, I'm going to put her on a ramp later this week and have a look.

---

Thanks for the response. My rattle was initially over across the whole rev range but only during acceleration. I've experienced this while my car was stock and I had the dealer change the turbos. These turbos are about 15K kms old. The DPs have definitely made the sound more noticeable. Not sure how true this is though. Now that I'm using "19" on menu 10, it seems to be restricted to around 2500rpm tp 3500 rpm or so. However now its acceleration and deceleration.

As for menu 12, I have tried to play with this but I see that BMS advises the 2400rpm to 2800rpm range. Tried all settings in between with no significant result.

What you saying with respect to the fix lines up with all the research I've done thus far. I've already requested some info on the actuators. While that's going on, I'm going to check out the actuator rod and maybe do the adjustment (with someone who knows their way around these turbos).

That being said... any assistance from a durban based fanatic who's been through this before would be appreciated.

 

[Kish2604]

i second/third and forth what Acheron has said... the reason for waste gate rattle is because the waste gate shaft into the turbo housing has worn away.... however if you say the dealer replaced turbos 15k kms ago i would remove your mods and take it back to them for a call back...

other than that tightening the actuator rods might help slightly but be careful of over tightening them...

 

[Donny_G]

Ok so here's the update:
- Put the car on the ramp and found that one of the exhaust gaskets that connect the dp to stock exhaust had blown (this was becoming more apparent as the days went by). We had no replacement gasket so did a temporary fix with gun gum. New gasket to follow.
- The rattle was still there so had the rear wastegate adjusted a bit. Helped a bit but still no good under low rpm and on deceleration.

At this point I was losing my mind! Installed the usb cable and then updated the the firmware(V 31.7). What an immediate difference. Rattle gone and car is hauling as well. There is still a slight intermittent surge but thats a topic on for another day.

If you're suffering with a wastegate rattle... definitely try the firmware upddate.

 

[akash]

Yepp i did the firmware update.

The rattle reduced quite a bit.

But you will never get rid of it though, if you running stock turbos.

 

[KrS24]

Did you notice any surging after the adjustment?

 

[Donny_G]

No. Before that. Been there from the first day I installed the mods.

Codes:
- 29E1 : fuel mixture control 2. This code has been coming up often and after erratic acceleration and jerking.

- 29D2: misfirings cylinder 6. This only started yesterday and man was it a kak experience. After 4th gear WOT, the car started vibrating badly. Actually thought that I had a flat tyre at one stage. Turns out it was tbis error. Restarted and was gone. But code has come back.

 

[cde_Lucky]

Wastegate rattle on N54's is a common & acknowledged hardware issue. Fr&RTuning sorted mine by triming them and via jb4 controls

Sent from my SM-N9005 using Tapatalk

 

[Mike-R]

This might have been discussed here but i am too lazy to read through the comments. :rollsmile:

Use settings 4 left and 5 right to force can flap open. My wastegate rattle completely disappeared when i used these settings..