Plenum/Intake follow thanks and follow up
#1
Instructor
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First of all, thank you guys for explaining to me the process for removing/replacing the boots on my '85 that connect the plenums to the intake (it is the intake, right?) It was as easy as you described. Now I am reinstalling and have two questions.
First, the 8 smaller boots all fit flush with the ridges on both the plenum and the intake pipes. However, the larger boots for the center pipes do not. In other words, if I make it flush with the intake, there is no "boot" left for the plenum. I ordered some new from 928 intl when I got the 8 smaller ones but they forgot to include them in the shipment. They will arrive, I hope, next week. Putting the old ones back on in the meantime but don't understand why they can't be flush with both the plenum and the intake pipe ridges. To have boot on both, I have to put it on 1/2 way on each. Wrong size boots at some point?
A BIGGER question is with this larger center pipe on the intake. When putting the boot on I noticed the pipe "wiggled" and in fact I can pull it up from whatever it is inserted to below. It appears that only a small hose would prevent me from removing it altogether. I am wondering if this is normal or whether this pipe is supposed to be more secure than it it. Perhaps when the plenums are all attached that is enough to hold everything together, but it seems to me that it being so loose would result in some sort of leak; oil, vacuum or otherwise.
As always, please forgive the novice questions and perspective. Renewing membership next week!
First, the 8 smaller boots all fit flush with the ridges on both the plenum and the intake pipes. However, the larger boots for the center pipes do not. In other words, if I make it flush with the intake, there is no "boot" left for the plenum. I ordered some new from 928 intl when I got the 8 smaller ones but they forgot to include them in the shipment. They will arrive, I hope, next week. Putting the old ones back on in the meantime but don't understand why they can't be flush with both the plenum and the intake pipe ridges. To have boot on both, I have to put it on 1/2 way on each. Wrong size boots at some point?
A BIGGER question is with this larger center pipe on the intake. When putting the boot on I noticed the pipe "wiggled" and in fact I can pull it up from whatever it is inserted to below. It appears that only a small hose would prevent me from removing it altogether. I am wondering if this is normal or whether this pipe is supposed to be more secure than it it. Perhaps when the plenums are all attached that is enough to hold everything together, but it seems to me that it being so loose would result in some sort of leak; oil, vacuum or otherwise.
As always, please forgive the novice questions and perspective. Renewing membership next week!
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#2
Three Wheelin'
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The center boot that goes over the throttle body should have 2 large hose clamps to hold it in place. It may shift a little when tightened up. Putting the rest of the spider together will snug things up.
As for the other 8 boot's I didn't realise there were different sizes? PET shows the same boot for all 8 runners. Mine fit about 1/2 way onto the plenum and the rest on the runner. As long as the hose clamps are tight you should be good to go.
As for the other 8 boot's I didn't realise there were different sizes? PET shows the same boot for all 8 runners. Mine fit about 1/2 way onto the plenum and the rest on the runner. As long as the hose clamps are tight you should be good to go.
#3
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First, the 8 smaller boots all fit flush with the ridges on both the plenum and the intake pipes. However, the larger boots for the center pipes do not. In other words, if I make it flush with the intake, there is no "boot" left for the plenum. ....
A BIGGER question is with this larger center pipe on the intake. When putting the boot on I noticed the pipe "wiggled" and in fact I can pull it up from whatever it is inserted to below. :
A BIGGER question is with this larger center pipe on the intake. When putting the boot on I noticed the pipe "wiggled" and in fact I can pull it up from whatever it is inserted to below. :
#4
Captain Obvious
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Yup, that's right. As strange as it is, the two large center boots have to be centered by eye. I have no idea why Porsche put the ridges so far back.
#5
Instructor
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The 8 boots are the same size, it is the center boots the cause the concern.
Ed, the center pipe I referred to is EXTREMELY easy to move. As I mentioned I am sure that if I removed whatever hose is attached to it it would come out easily. Do you think that as loose as this is that it could cause difficulty in starting in cold weather and a very rough idle? Also, the car is presently not passing my states emissions requirements. Do you think that as loose as this is that I could be having some type of vacuum leak?
Finally, if you could give me any direction as to how I get to and tighten the clamps you mentioned I would appreciate it.
I am on my third beer. Thank you very much.
Ed, the center pipe I referred to is EXTREMELY easy to move. As I mentioned I am sure that if I removed whatever hose is attached to it it would come out easily. Do you think that as loose as this is that it could cause difficulty in starting in cold weather and a very rough idle? Also, the car is presently not passing my states emissions requirements. Do you think that as loose as this is that I could be having some type of vacuum leak?
Finally, if you could give me any direction as to how I get to and tighten the clamps you mentioned I would appreciate it.
I am on my third beer. Thank you very much.
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#6
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Patrick - it should not be that loose. There should be a clamp holding it at the bottom to the throttle body - find the screw and tighten it up snug. This could be the cause of some of the problems you are having.
#7
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Thanks Ed. At this point I almost have it all back together so I think I will follow your suggestion when the other two boots come in. Can you tell me if I will have any problem getting to what needs to be tightened? Anything else that will have to be removed. Once. again thank you so much
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#9
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Thanks everyone. Not sure, Marton, if the later engine will make things as easy on my '85 as on your '82 but hope so and will find out! FYI, after installing the new boots, except for the center ones, the car starts. idles and runs 100% better. Taking it to get the emissions test tomorrow with my fingers crossed. Thatnks to everyone for all of your help. You guys have certainly saved me 100's of dollars and probably 1000's! THANK YOU JESUS!
#10
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keep us posted - and good luck!
#11
Burning Brakes
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Once you have all the hoses connected and the clamps tight the center tee should be fairly snug but it is only mounted in rubber so not rigid. If it is as loose as your description I wonder if your throttle body is no longer attached to the block. In my case the two studs (actually little in line rubber mounts) were sheered off letting the throttle body move more than it should.
#12
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Thank, Roger and everyone else. I am going to discoonect everything again within a week and hope I will be able to take a better look at how it is sitting. I can see a bit of it with everything in place but not enough to have a good idea of what might be wrong. Could that rubber mount be bad?
#13
Burning Brakes
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There are two isolation mounts that connect the throttle body to the engine block. The one on the throttle rod side is visible but the one on the other side is buried.
When you take the center tee back off to replace the boots reach down in the hole and grab hold of the throttle body and see if it is basically secure or free floating. If it is secure, them when you reassemble the Tee make sure that the boot on the bottom that connects to the throttle body is secure.
On my '85 both throttle body mounts were sheered off. At first I thought the thottle body just sat there on supports and was held in position by all of the other connections but I was wrong. In my case the fix was easy because I pulled all of the intake pipes off to powder coat them, clean the valley, replace all the vacuum lines, etc. etc.
Keep us posted.
When you take the center tee back off to replace the boots reach down in the hole and grab hold of the throttle body and see if it is basically secure or free floating. If it is secure, them when you reassemble the Tee make sure that the boot on the bottom that connects to the throttle body is secure.
On my '85 both throttle body mounts were sheered off. At first I thought the thottle body just sat there on supports and was held in position by all of the other connections but I was wrong. In my case the fix was easy because I pulled all of the intake pipes off to powder coat them, clean the valley, replace all the vacuum lines, etc. etc.
Keep us posted.
#14
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Thanks, Roger. I will be attacking it this weekend. Do the intake pipes come off fairly easily? I'm just trying to think ahead so that if I need to get to the throttle body I'll be ready to do so. I went ahead and ordered the boot on the bottom that connects to the throttle body. Eyeballing the area as best I could seemed to reveal lots of oily residue in the area and I'm wondering if after 200K plus miles it might be prudent to replace this ... among other things.
#15
Burning Brakes
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To remove the intake pipes you need to remove the fuel rails and injectors. The bolts that hold them to the heads are esy to access once the fuel rails are out of the way. In my case that was fine because I was doing a complete refurbish and sent my injectors out to be cleaned and flow tested and .... and ... you get the picture. Unless you want to dig that deep I would leave the pipes in place. There should be a clamp on both ends of the boot that connects the throttle body to the Tee. One is easy because the Tee is not in place... the other one is a pain but I was able to access the clamp screw from the back with the bottom of the air cleaner removed.
If your fuel lines have not been replaced it would be a good place to start. There are to many stories about cars being lost due to fuel fires. Do a search there are a lot of good posts regarding fuel line replacement.
If your fuel lines have not been replaced it would be a good place to start. There are to many stories about cars being lost due to fuel fires. Do a search there are a lot of good posts regarding fuel line replacement.