wasabiskier

I noticed the lovely rattle of washers coming from my turbo when I back off the throttle at low speeds or rev the engine at idle. Further inspection reveals some play in the wastegate lever/rod on the outside of the turbo. The rattling washers are internal to the turbo. The external lever seems to control the "actuation" of the wastegate flap? This lever is driven by a rod extending from the wastegate actuator. There are two nuts on the lever end of the rod that can be adjusted to increase or decrease the effective location of the lever to rod connection. I can feel the play at this connection as well and assume that a slight shortening adjustment will remove the play and eliminate the rattle. My concern is two fold:

A) Bentley specifically states no adjustment should be made to these nuts.

B) Is this play a result of a failing/deteriorating wastegate actuator that is not pulling or allowing the wastegate to close fully. I am not certain whether the flap is spring loaded and the actuator works against a spring to open the flap when the desired boost is reached or whether the flap is unsprung and requires the actuator to hold the flap closed as well as hold it open.

Does any of this make sense? My turbo seems to still boost well except the turbo lag seems markedly longer, (1st and 2nd gear don't reach full boost until well after 4k RPMs), which may suggest the wastegate is not closing fully/completely. Ofcourse I now live in Denver (read as thin air) instead of Maryland (sea level) so I would expect a negative effect on turbo lag.

As always, any thoughts are greatly appreciated.

Regards,

Lorin

BSCA4

they need to be tighten. What I would do will be loosen the inner nut, tighten the outter nut to a point you start have some tension on the waste gate then add 2 turns. After that tighten the inner nut.

envuks

i believe i have the same problem. how difficult is it to access the waste gate?

wasabiskier

Thanks. I will give that a try and let everyone know how it goes. If I over-tighten or screw up the setting too much, what is the downside? Bad boost control? Over boosting? I thought the ECU controlled the top end boost using the wastegate and some sort of feedback loop.

wasabiskier

Hey guys,
I tore the turbo out this weekend to see if I could adjust those nuts. After inspection I realized adjusting them is not going to help since the internal wastegate is thrashed (significant wear on the flap and play in the rods). I am now in the market for a low to medium mileage used turbo. I am not planning to upgrade since the car has 118k on it. Is it worth a rebuild on the turbo? Can they replace the wastegate or does the whole housing need to be done. There doesn't seem to be any play in the turbines or shaft so I am hoping just to get the wastegate fixed and keep the car alive for XX more miles.

Thanks!!

Lorin

wasabiskier

Bump

Mike Oosterhuis