Turbo's wastegate actuator rod related rattle in NMS possible?

[Brad95]

having this issue for long time., even left @ dealer for few days but they could not replicate. i have searched everywhere but did not find any similar issue with any NMS nor the solution!

rattle noise comes from the passenger side front area and comes on at light to medium throttle at low RPM's. with light to moderate load. Rattle comes when RPM is low with high gear (4th or 5th gear and 1100 rpm and when it reach between 1200-1400, let go gas pedal for second or two without pressing clutch) with moderate incline. Usually happens when you accelerate away, part throttle (so you don't build your rev too fast and out of the "zone"), and between 1-3k you'll hear this “rustling leaves” rattle.


initial thought, was something must be loose behind glove compartment. so removed glove compartment & other trim panels and test drove with friend driving and myself sitting on passenger side. drove a quiet of bit on hilly roads. found out, rattle was coming from engine compartment right where turbo is located.


For similar issue there was TSB (2024061) but it was for “CBFA” & “CCTA”. It stated "Exhaust gas pulsations can cause the wastegate flap and actuator rod to vibrate at the introduction of boost pressure"


does CKRA engine has same turbo setup as CBFA & CCTA?

i don't know how helpful it is! but found this @ vortex http://forums.vwvortex.com/showthread.php?5194069-Wastegate-Actuator-Rod-rattle-SOLVED

 

[Spyke]

All Passat I've tried (gas or diesel) 4 cyl to v6, they all do that. Automatic to manual transmission.

I think its the abs system preparing for emergency braking since we have brake assist on our cars!

Its the exact same sound as if you drive more than 35 mph, setting the wipers to intermittent and you'll hear the same rattle/noise every 2 minutes or so (abs engaging a little bit to dry the brake pads and rotors).

If you search in the Passat forum, you'll find discussions about that.

-Mark

 

[nord]

You're not going to like what I'm about to share and I certainly hope I'm wrong...

My '13 developed a sound similar to what you're describing just before the turbo lost its feathers. I assume the actuator was attempting to adjust vanes which were getting increasingly reluctant as the failure progressed.

I'm not trying to be an alarmist here. All I'm saying is that while you may have an innocent problem, there's also a good chance that your car is giving fair warning of a very serious impending failure.

Personally I'd opt for preventative measures and check the turbo for runout and oil leaks. If you find that all is well, then at least you can take comfort in the fact and assume the TSB is probably describing your immediate problem. On the other hand if a failing turbo, then you'll have potentially saved your entire engine under worst case conditions and at least saved a major inconvenience if a less severe failure.

(Addendum)

After viewing the above post where mention of the braking system was made, I felt it deserved comment. There will be a slight fluttering sound made IF your wipers are activated. This "fluttering" noise will come at regular intervals and is associated with the ABS module slightly applying brakes in order to keep the rotors dry. It's much different than the actuator sound which at the end stages of failure will sound like a stripped gear being run over a rack.

 

[TurboDieselPoint]

I'll second the idea that its the ABS lightly pulsing the brakes when you release the accelerator.

My car does it occasionally when let off the accelerator abruptly, even if the wipers are not on. It is simply the ABS preparing for an emergency stop.

Read to the bottom of this thread for more details: http://forums.tdiclub.com/showthread.php?t=407572&page=2

Good luck!

TurboDieselPoint

 

[VeeDubTDI]

I don't know if it's the ABS, noise from the charge air system, or something completely different, but I wouldn't be worried about it.

The CFBA and CCTA engines are gassers and have zero similarities to the TDI, especially in this situation because the TDI doesn't have a wastegate (it uses a variable nozzle turbine housing).

So the answer to your question is NO, it is absolutely 100% not related to the wastegate actuator control rod.

 

[jck66]

Dang, you stole my thunder VeeDub!

 

[TDIEQNY]

Ive had a noise similar to this since new.

comes and goes... under load but not at all times

sounds almost like a lifter tick...

Have ignored it.

 

[Bug Smasher]

I think I've been experiencing the same thing since new...Almost 10k miles on the odometer right now; no issues so far.