[-paul]

Hi all, new here. I've owned my 335i since August last year and I love it but I'm looking for tips and knowledge regarding my next step. It's just ticked over 70k miles and it's a manual.

I have the dreaded/common waste gate rattle but has become extreamly obvious when letting off the throttle coming down the revs and also when accelerating now (but not quite so loud when accelerating). When I disconnect the vac line from within the engine bay, the rattle does disappear when driving around. Also I can here a turbine spool up as accelerating in 2nd gear only which is weird but apparently that's common and mean rear turbo on the way out.

I've also recently spent just over £1000 on having new oil feed pipes, o rings, gaskets etc replaced as I had a bad oil leak and the whole of my under tray was covered! Which certainly damaged the wallet.

I have a couple of questions.

1. I'm assuming replacing the turbos is the only 'proper' fix. Do I stick with OEM or do I go aftermarket/hybrid? If so why and good reliable places to buy from and have work done. I'm located in South East.

2. Secondly, and this is almost completely off topic, I've been reading up on jb4 from n54 tech, and I'm pretty much sold. Do many of us from the UK run jb4? Some of the extra features and adjustments appear to be great. Read/delete codes, different maps etc. and I've also heard it can help reduce waste gate rattle by tweaking some settings but I understand it will not be a fix as such. Especially mine as they're pretty bad.

On the plus side, my car appears to still be boosting well. Although on 3 separate occasions since owning the car I've must of covered no more than 2/3k miles (not a daily driver) and its gone into limp mode when pulling hard in 3rd gear and shifting into 4th. Not quite sure what that is as it has only done it on 3 separate occasions and it goes away once I restart the car.

Thanks in advance
Paul

[RajB]

Hi Paul and welcome aboard.

The actuators that actually cause the rattle can be replaced with dealer replacements depending upon year. I know my mates 135i (59 plays) was the case. It was far cheaper than having to replace the whole turbo. So that's the first thing to consider/find out.

If going aftermarket then there are options out there such as Turbo Dynamics or RB. There is a thread in the main section regarding recent upgrades by fellow members.

I run the JB4 as do a lot of guys here. They are an excellent bit of kit and allows a lot of customisation as well as being well pre-set for future upgrades such as meth or turbo etc.

Hope that helps,

Raj.

[-paul]

This has helped a lot, thanks for your reply!

[Cerbera9]

From my experience and research the actuators are not the problem or the cause of the wastegate rattle.
The problem is caused by wear where the wastegate pivot arm goes through the turbo housing causing play in the arm and thus the rattle. The JB4 and BMW software udates only adjust the vacuum applied via the solenoids to the actuators and the therefore the load placed upon the wastegate arms to minimise the play in the arm and hence reduce the rattle. Please note that this is only a temporary fix until the wear increases and the rattle returns in the long term.
The rear actuator can be adjusted whilst in place although it is a PITA to do. The front turbo actuator requires removal of the turbo to get to the actuator rod to adjust it, ideally you will need to remove the DP's in order to check with a Vac gauge that both wastegates are closing simultaneously. if your going to this much trouble and removing the front turbo & DP's in my opinion you might as well have both turbos off and overhauled to cure the rattle problem once and for all. Failure to adjust and set both actuators correctly will cause boost issues.
The likes of RB Turbos use Upgraded New Billet INTERNAL wastegate assembly and Turbo Dynamics Bespoke TD wastgate assemblies, to eliminate the wastegate rattle issues.
In extreme cases if the wastegates doesn't close and seal correctly the turbo will continuously bleed off boost down the DP's and struggle to reach boost target, this results in the ECU requesting more boost via the solenoid and the turbo actually overboosting as it struggles to make boost target. This can lead to premature bearing & seal failure.

[Cerbera9]

I also run JB4 its a great bit of kit and I have used the rattle fix you mention however is will reduce the response of the turbos.
From experience if you are replacing the turbos the only way forward is aftermarket turbos with upgraded wastegate assemblies it doesn't cost that much more to do that OEM turbos and the benefits outweigh the cons.

[Cerbera9]

Originally Posted by -paul

Hi all, new here. I've owned my 335i since August last year and I love it but I'm looking for tips and knowledge regarding my next step. It's just ticked over 70k miles and it's a manual.

I have the dreaded/common waste gate rattle but has become extreamly obvious when letting off the throttle coming down the revs and also when accelerating now (but not quite so loud when accelerating). When I disconnect the vac line from within the engine bay, the rattle does disappear when driving around. Also I can here a turbine spool up as accelerating in 2nd gear only which is weird but apparently that's common and mean rear turbo on the way out.

I've also recently spent just over £1000 on having new oil feed pipes, o rings, gaskets etc replaced as I had a bad oil leak and the whole of my under tray was covered! Which certainly damaged the wallet.

I have a couple of questions.

1. I'm assuming replacing the turbos is the only 'proper' fix. Do I stick with OEM or do I go aftermarket/hybrid? If so why and good reliable places to buy from and have work done. I'm located in South East.

2. Secondly, and this is almost completely off topic, I've been reading up on jb4 from n54 tech, and I'm pretty much sold. Do many of us from the UK run jb4? Some of the extra features and adjustments appear to be great. Read/delete codes, different maps etc. and I've also heard it can help reduce waste gate rattle by tweaking some settings but I understand it will not be a fix as such. Especially mine as they're pretty bad.

On the plus side, my car appears to still be boosting well. Although on 3 separate occasions since owning the car I've must of covered no more than 2/3k miles (not a daily driver) and its gone into limp mode when pulling hard in 3rd gear and shifting into 4th. Not quite sure what that is as it has only done it on 3 separate occasions and it goes away once I restart the car.

Thanks in advance
Paul

If you disconnect the vac lines there will be no vacuum to close the wastegates, therefore the turbos will still spin and any boost produced will be going straight down the exhaust, this is what you can hear.

[-paul]

Originally Posted by Cerbera9

From my experience and research the actuators are not the problem or the cause of the wastegate rattle.
The problem is caused by wear where the wastegate pivot arm goes through the turbo housing causing play in the arm and thus the rattle. The JB4 and BMW software udates only adjust the vacuum applied via the solenoids to the actuators and the therefore the load placed upon the wastegate arms to minimise the play in the arm and hence reduce the rattle. Please note that this is only a temporary fix until the wear increases and the rattle returns in the long term.
The rear actuator can be adjusted whilst in place although it is a PITA to do. The front turbo actuator requires removal of the turbo to get to the actuator rod to adjust it, ideally you will need to remove the DP's in order to check with a Vac gauge that both wastegates are closing simultaneously. if your going to this much trouble and removing the front turbo & DP's in my opinion you might as well have both turbos off and overhauled to cure the rattle problem once and for all. Failure to adjust and set both actuators correctly will cause boost issues.
The likes of RB Turbos use Upgraded New Billet INTERNAL wastegate assembly and Turbo Dynamics Bespoke TD wastgate assemblies, to eliminate the wastegate rattle issues.
In extreme cases if the wastegates doesn't close and seal correctly the turbo will continuously bleed off boost down the DP's and struggle to reach boost target, this results in the ECU requesting more boost via the solenoid and the turbo actually overboosting as it struggles to make boost target. This can lead to premature bearing & seal failure.

Thanks very much for your replies.

So I guess the cheapest repair is to have the rods replaced rather than the turbos, as long as my turbos are ok. Although I have a friend who's replaced his OEM turbos for aftermarket so if I could buy his old OEM turbos off him (as his have done lower mileage but also suffer from the rattle) I could have them repaired and then just pay the cost to have them switched over. Is there a permanent fix when having the rods/turbos overhauled when sticking with OEM turbos? Or am I to expect the rattle to come back eventually?

Otherwise, if I went ahead and changed the turbos with aftermarket, how much am I looking at spending to purchase them and have them fitted, on average?

Basically I'm in a slight dilemma. My first baby is on the way and my fiancée and I have agreed to give the Coupe a try and see how we manage with having only 2-doors (having a fixed baby seat in the back) etc etc but there is a chance it may become awkward eventually, so a saloon would perhaps be a better option.

One thing I have agreed on is to stick with a 335i. So it's either I repair this rattle on my car and keep it for the foreseeable future or I switch to a 335i saloon.

Many thanks in advance.

[Cerbera9]

The OE turbo is not the problem. its the OE wastgate assembly that wears and causes the rattle. New OE turbos with OE wastegate assemblies will rattle eventually. New actuator rod ends can be purchased but rarely solve the problem and the front actuator is inaccessible unless the turbo is removed. Plus the actuators/wastegate will then require setting up correctly and that requires the DP removal.

You can buy new replacement turbos for about £600 per turbo. Someone like Turbo Dynamics and stage 1 hybrid your original turbos including new wastegate assembly to cure the rattle from £750 per turbo. I would expect to pay £600-£1000 (approx. 10hours book time removing and refitting the turbos) by the time you've replaced any lines, gaskets, thermostat, fluids and anything else you find along the way whilst the turbos are out so budget accordingly. I found the easiest way was to have the engine and gearbox removed, that way the turbo removal was easier and the clutch could be done at the same time so cutting down on labour cost in the long run.

[-paul]

Originally Posted by Cerbera9

The OE turbo is not the problem. its the OE wastgate assembly that wears and causes the rattle. New OE turbos with OE wastegate assemblies will rattle eventually. New actuator rod ends can be purchased but rarely solve the problem and the front actuator is inaccessible unless the turbo is removed. Plus the actuators/wastegate will then require setting up correctly and that requires the DP removal.

You can buy new replacement turbos for about £600 per turbo. Someone like Turbo Dynamics and stage 1 hybrid your original turbos including new wastegate assembly to cure the rattle from £750 per turbo. I would expect to pay £600-£1000 (approx. 10hours book time removing and refitting the turbos) by the time you've replaced any lines, gaskets, thermostat, fluids and anything else you find along the way whilst the turbos are out so budget accordingly. I found the easiest way was to have the engine and gearbox removed, that way the turbo removal was easier and the clutch could be done at the same time so cutting down on labour cost in the long run.

Thank you for the info! Appreciated!

I guess if Turbo Dynamics stage 1 the turbos with a better waste gate assembly, then I'd rather spend the money on that if it means a permanent fix? I may give them a ring and have a chat with what they can do for me.

Thanks again mate, you've given me options I wasn't aware of! I've been reading some thread with people upgrading turbos from turbo dynamics but didn't realise they can 'hybrid' existing turbos.

Cheers

[Cerbera9]

No problem, You may find this thread interesting reading http://www.e90post.com/forums/showthread.php?t=1100560