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I'll just jime in with a quick question. Regarding the last post, i guess its possible to remove the whole Throttle bodies from one bank, replace the gasket beneath it and just screw it back on the head.

I never considered the O-rings between the throttle bodies. Should one replace these? Or is there usually not a problem with them?

And finally, the question i was actually going to ask: The throttle positioner (the thing in the middle which controls the individual throttle bodies). Can i remove it and install it again without having to sync the left and right bank (I am installing the same positioner again)?

Thank you
Yes you can just remove the motor/actuator by itself, I had to remove it to replace some of the hoses. The threaded rods (13541407960 & 13541407396) that go from the actuator to the throttle body linkage can't rotate accidentally, so if you just move them to the side they will not affect position. UNLESS, for some reason, the rod is already loose or you decide to loosen/unthread the lock nut.

The reason I want to change the o-rings is because I had to rotate the hard T-connector (13417830410) that goes from bank-1 to the evap rubber hoses. I don't have any codes, but I bought them with the intention of changing them from the begining. Also the tiny vaccum hose (? 11727545323 ?) that goes to the tiny-tiny bank-2 barbed fitting has hairline cracks and I need to replace it.
 

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If you mean the actuator then yes replacing does not require sync even if it is a new one.
I don't think the second part of this is true. Yes, you can remove the actuator and reinstall without re-synching (I do this every time I delete the heat exchange underneath or to replace the fuel purge valve), but replacing it with another unit or a new unit will require synching or at least calibration using DIS or ISTA, I believe.

Calibrating it with the software tells it how much voltage is needed to pull the throttles to 1% for idle. This is all according to the TIS documents. So may or may not be needed.
 

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but replacing it with another unit or a new unit will require synching or at least calibration using DIS or ISTA, I believe.
Yes that is right you have to set up that new actuator. That has nothing to do with syncing the throttles though. Syncing the throttles is basically having them open all at the same time. The actuator is independent of the throttles as individuals it is an adjustment for the whole group. Syncing the throttles is nothing in DIS or INPA it is mechanical measurement. That said there is a test you can do and if you did it wrong DIS will tell you but that has more to do with doing the first step correct. If you do the first step wrong which is the relationship to the actuator. Sort of like a vanos test, does not help you fix it just tells you it is broken.
 

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Thanks for the answers. That makes it a lot easier when i can dissassemble the parts and just put them back on once i am finished. Its good because that way i can redirect all my prayers to the vanos god for that he does not bend my valves and do not need to split prayers between the vanos god and the throttle body god.
 

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Yes that is right you have to set up that new actuator. That has nothing to do with syncing the throttles though. Syncing the throttles is basically having them open all at the same time. The actuator is independent of the throttles as individuals it is an adjustment for the whole group. Syncing the throttles is nothing in DIS or INPA it is mechanical measurement. That said there is a test you can do and if you did it wrong DIS will tell you but that has more to do with doing the first step correct. If you do the first step wrong which is the relationship to the actuator. Sort of like a vanos test, does not help you fix it just tells you it is broken.
I don't disagree with anything you're saying. I understand the sync process, I actually have the BMW tool for it, I'm just saying that TIS says to synch the throttles if you replace the actuator. Part of the synch process is adjusting the rods that pull the banks. So maybe that says that not all actuators rest at the same location.
But TIS also says some other wild sh!t, like removing the cylinder heads to do a chain guide job lol. So there's that...
 

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Part of the synch process is adjusting the rods that pull the banks.
Not sure I would agree that it is part of the syncing process unless you have to do the sync anyway. Sort of like jacking the car up to get the tranny out. Yes you must jack the car up, but you don't say that anytime you jack the car up you are doing the tranny removal. OP did not use DIS if I recall.
Besides that the syncing process is way over done. Before I even started to do this oring replacement I got out my calculator and decided how much a butterfly had to be out to make a difference. I still put things back to the way they were but only needed vernier calipers, digital but still. Even if you were out a visually noticeable amount the ICV system will still balance the vacuum to the cyls. There was also more chance of differences in the air path to the throttles than a minor difference in throttle butterflies, lets just say 10 thous for the sake of it. Besides there is no way to know where the air flowing threw the tubes and into the throttles is laminar and where it is disturbed, that will have a bigger effect than someone being 10 out.
Lots of us have replaced actuators by just adjusting the rods and not doing anything more. I don't see how that would be considered that is you do that you would have sync'ed the throttles, because you have not done that in anyway. All you have to do is read the first post to see that there is way more to syncing the throttles than adjusting those rods.
 

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Lots of us have replaced actuators by just adjusting the rods and not doing anything more. I don't see how that would be considered that is you do that you would have sync'ed the throttles, because you have not done that in anyway. All you have to do is read the first post to see that there is way more to syncing the throttles than adjusting those rods.
I don't know where you're getting any of this from. That's not what I said.

1. I understand the whole sync process and how involved it is.
2. I said that part of the sync process is measuring and adjusting the rods. Just look at the TIS document. That's what I'm referring to.
3. I'm not disagreeing with anything you're saying. I'm just referring to what BMW TIS calls out for, while also recognizing that they occasionally make you do extra unnecessary steps.
 

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This is what you said and this topic and the conversation that was taking place was about adjusting all 8 throttles to open at the exact same time. It was not about syncing to the throttle mass. You don't have to touch anything other than the actuator rod to install a new actuator. The syncing process we are talking about is the adjustment of the throttles not the actuator.
I don't think the second part of this is true. Yes, you can remove the actuator and reinstall without re-synching (I do this every time I delete the heat exchange underneath or to replace the fuel purge valve), but replacing it with another unit or a new unit will require synching or at least calibration using DIS or ISTA, I believe.

Calibrating it with the software tells it how much voltage is needed to pull the throttles to 1% for idle. This is all according to the TIS documents. So may or may not be needed.
 
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