Idle problem after vacuum repair
#16
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Do you have the workshop manuals? If not down load from :
http://www.2010.cannell.co.uk/manual...s_porsche.html
scroll down for the 928 section, you need to study section 1A group 24.....
Last edited by neilh; 03-17-2014 at 04:26 PM.
#18
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I assume you mean 11 ( which is the mechanical connection from the tempostat tank) goes to the throttle linkage, it is not an air line. Is the 'Y' from line 24 to the 4 way broken, its a common failure. What part are you calling a 'pot'?
#19
Intermediate
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The red vacuum hose according to my picture..don;t have a clue whats that called
sorry.
Btw could a vacuum leak inside, behind the dash cause this idle stall problem ?
Funny thing is i never touched anything
.
When i have the engine running for a few seconds vacuum builds up...
when engine is not running i pul one hose from the 4-way connector and i hear it sucking air, so i asume a vacuum is build in that system.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Btw could a vacuum leak inside, behind the dash cause this idle stall problem ?
Funny thing is i never touched anything
![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
When i have the engine running for a few seconds vacuum builds up...
when engine is not running i pul one hose from the 4-way connector and i hear it sucking air, so i asume a vacuum is build in that system.
#20
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The red vacuum hose according to my picture..don;t have a clue whats that called
sorry.
Btw could a vacuum leak inside, behind the dash cause this idle stall problem ?
Funny thing is i never touched anything
.
When i have the engine running for a few seconds vacuum builds up...
when engine is not running i pul one hose from the 4-way connector and i hear it sucking air, so i asume a vacuum is build in that system.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Btw could a vacuum leak inside, behind the dash cause this idle stall problem ?
Funny thing is i never touched anything
![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
When i have the engine running for a few seconds vacuum builds up...
when engine is not running i pul one hose from the 4-way connector and i hear it sucking air, so i asume a vacuum is build in that system.
I would pull the line going into the car and plug it, and the line to the heater control and plug it, also the lines going to the tempostat and plug them..
Leave only the red lines in the first diagram connected, they are all you need to get it to create vacuum to run. Also check the metal line coming off the front of the main metal plenum. It goes to the auto transmission, if it is broken you will also have a leak.
I have an identical 84 euro here, i can take a look tomorrow and see if anything else is obvious.
#21
Intermediate
Thread Starter
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The suction at the 4 way is a good sign.
I would pull the line going into the car and plug it, and the line to the heater control and plug it, also the lines going to the tempostat and plug them..
Leave only the red lines in the first diagram connected, they are all you need to get it to create vacuum to run. Also check the metal line coming off the front of the main metal plenum. It goes to the auto transmission, if it is broken you will also have a leak.
I have an identical 84 euro here, i can take a look tomorrow and see if anything else is obvious.
I would pull the line going into the car and plug it, and the line to the heater control and plug it, also the lines going to the tempostat and plug them..
Leave only the red lines in the first diagram connected, they are all you need to get it to create vacuum to run. Also check the metal line coming off the front of the main metal plenum. It goes to the auto transmission, if it is broken you will also have a leak.
I have an identical 84 euro here, i can take a look tomorrow and see if anything else is obvious.
so in fact just pul the main hose small one from the breakbooster and plug it.
then see if it works with only the fuelvacuum system connected.
but this vacuum comes from the carb system.
#22
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Correct, that should take any leaking or miss-placed vacuum lines out of the problem. Oh, its not a carb, its a fuel injection throttle assembly
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Neil
#24
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#25
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Air temp sensor in air filter box, should not be the cause of this problem.
#27
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#28
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Have you done a smoke check?
Just like it sounds: blow smoke into a vacuum line and see there it comes out. A bad cigar will work nicely.
Really helps find those mistakes on reassembly when you are sure it's right.
Just like it sounds: blow smoke into a vacuum line and see there it comes out. A bad cigar will work nicely.
Really helps find those mistakes on reassembly when you are sure it's right.
#29
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