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Throttle Body 987.1Schematic

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Hello Everyone new here. I have a six peed 2005 Boxster S that had a broken throttle body 6 pin connector purchased a new six pin connector and solder it into the remaining wires per the Bentley manual schematic.Does anyone know where I can get a year specific schematic of the wiring of the throttle body?  The car will start and run for about ten seconds prior to starting I did the computer reset per the instructions.  When it starts out in the ten second period it stumbles a little bite then quits.  Any help will be deeply appreciated suppose to take the grand daughter on a long trip leaving on Sunday 8/6.


Thank you all;


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Well today I am going to measure the voltage and resistance on the throttle body plug pins to see if there is any short somewhere since this is getting so much attention here.  Prior to posting here I contacted Bosch Automotive to see if they had an answer they say that this information is property of Porsche and confidential, that is when they would reply.  I know this forum is more technical than most forums where they want to know what is the largest tire I can put on the car or how to change this car to a turbo.  Please guys if you have any idea on how to resolve this problem please let me know.


Thank you;


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You need to understand that Bosch is correct in their response, Porsche stopped printing all factory service data years ago, and started shutting down websites that publish anything they feel is their intellectual property, so there is precious little information out there.  If you want to get the factory data, you need to start a subscription to Porsche's PIWIS TSI electronic technical information system, which will give you online access to the information you feel you need, but at a price.

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Thank you Gentlemen for all the information and JFP I can see your point they would rather have their Dealers take care of everything, they don't know their market very well it seems as though the majority of people enjoy working on their own cars, I have been following your post for quite some time.  I got a little bit closer today car runs now but will not go over two thousand RPM.  The first problem was the black elbow tube from the Throttle Body to the MAF was not quite tight enough a little opening at the bottom, fixed that.  


Testing the connector got 5 volts on all the pins on the Ohms readings I have to think more about that.  Tried starting it again had a small leak by the intake manifold fixed those and now I am at the not going over two thousand RPM problem, I remember in the past some else having that problem.  Loren and Ahsai thank you for the schematics same as what I was using.  Perhaps I would be better off just buying a used connector and then just match up the wires by color, the only thing is that people that hve these think they are losing money cutting up a wire harness.  

Thank you again all for the help, don't feel like I am on a raft in the middle of the ocean any more.




Gutten Tag

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P0638 is the code when the expected and actual position of the throttle blade does not match.  As this harness is very resistance sensitive, have you checked all the wires for high resistance (possible a bad solder joint)?


Porsche, by-the-by went electronic to protect their intellectual rights.  Historically, they have been very aggressive when anyone steps over that line, even shutting down websites for using their logos without written permission.

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Like John said above. That explained the "limp mode" cause the DME thinks the throttle body is no good. So it's either what John said or you have a bad throttle body.


There are two pots inside the sensor that move together. With Durametric under actual values, you should be able to see the voltage readings of these two pots (0 to 5v). If memory serves, one value is always half of the other or one is 5v minus the other.

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Everyone;  Still only getting Durametric error P0638 The car has the same problem with MAF or with it disconnected. no change, I guess I will need to order one of these.  Got a rental Ford Fiesta for our trip will get back to fixing the problem next week, Everyone have a wonderful week.




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  • 2 years later...
On 8/4/2017 at 5:26 PM, Loren said:

MY2005 throttle valve...

throttle valve.png


Can anyone tell me where the two wires disappear to from the above throttle valve motor wires , I’ve done a complete wiring check and from inside the boot (ecu mounted) all the wiring checks out correct but the two motor wires disappear into left hand side relay and fuse  Carrier inside top of rear wing ...

from there I cannot trace gy/bu gy/wh, plus where do I find TP 225 ? I presume a Test point , unable to locate as well,

any help would be gratefully received .

thank you 

Edited by Rob56
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