2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

1991 S5 Convertible vacuum line help

Thread Tools
 
Search this Thread
 
Old Oct 12, 2014 | 03:27 PM
  #1  
ThatGuyOnTheGas's Avatar
Thread Starter
Full Member
 
Joined: Nov 2013
Posts: 54
Likes: 0
From: Fort Leonard Wood, Mo
1991 S5 Convertible vacuum line help

Hey guys, I was putting my car back together after getting the fuel injectors cleaned, I got it all the way back together and then notice a couple of vacuum lines that aren't connected, one behind the air hose going from the air box to throttle body, I will refer to it as #1. The other looks like it is coming from the driver's side, under the lower intake manifold, #2. Line #1 is coming off a T that runs from the throttle body to the cruise control actuator. It's rather short, only a few inches, and doesn't look like it's ever been connected. Line #2 looks as if it's running from the driver's side, between the upper and lower manifolds to the passenger side. I've not been able to trace it backwards just yet, but it looks like it's been connected before. I'll attach pictures of both, first is the source of line #1, second is the end of line #1 and third is line #2
Attached Thumbnails 1991 S5 Convertible vacuum line help-line-1-source.jpg   1991 S5 Convertible vacuum line help-line-1-end.jpg   1991 S5 Convertible vacuum line help-line-2.jpg  
Reply
Old Oct 12, 2014 | 08:11 PM
  #2  
misterstyx69's Avatar
Retired Moderator, RIP
Tenured Member: 20 Years
iTrader: (142)
 
Joined: Sep 2005
Posts: 25,581
Likes: 136
From: Smiths Falls.(near Ottawa!.Mapquest IT!)
ok..two lines.
short one(with the T) goes to the White plastic thingie on the Throttle body.It would come from the vacuum rack.
The Green check valve line hooks up to the same plastic thing but also scoots across under the throttle body to a Diaphragm looking bell on the "front side"(TPS side) of the throttle body and hooks up there.
Reply
Old Oct 13, 2014 | 08:06 PM
  #3  
ThatGuyOnTheGas's Avatar
Thread Starter
Full Member
 
Joined: Nov 2013
Posts: 54
Likes: 0
From: Fort Leonard Wood, Mo
Originally Posted by misterstyx69
ok..two lines.
short one(with the T) goes to the White plastic thingie on the Throttle body.It would come from the vacuum rack.
The Green check valve line hooks up to the same plastic thing but also scoots across under the throttle body to a Diaphragm looking bell on the "front side"(TPS side) of the throttle body and hooks up there.
So then I should be able to just remove the throttle body and see where they should connect? Sorry for the late response, but I hardly have time between work class and sleep to get online
Reply
Old Oct 13, 2014 | 10:50 PM
  #4  
misterstyx69's Avatar
Retired Moderator, RIP
Tenured Member: 20 Years
iTrader: (142)
 
Joined: Sep 2005
Posts: 25,581
Likes: 136
From: Smiths Falls.(near Ottawa!.Mapquest IT!)
Actually if you remove the throttle body inlet(2-12mm chrome capped nuts) you should see the areas I am referring to.

That green check valve with hose sits on a small clip under but Attached to the throttle body.The hose runs directly under the TB,from one side(back) to the other(front of car).
It sort of connects the 2 "doo-dads" that are on opposite sides of the TB together.
Reply
Old Oct 14, 2014 | 05:52 AM
  #5  
ThatGuyOnTheGas's Avatar
Thread Starter
Full Member
 
Joined: Nov 2013
Posts: 54
Likes: 0
From: Fort Leonard Wood, Mo
But it looks like it's coming from under the lower intake manifold, from the driver's side, or could I just not have lifted it up when I was reassembling?
Reply
Old Oct 14, 2014 | 07:03 AM
  #6  
jjwalker's Avatar
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
The pics are small so I can't really tell, but is it just me or does it look like his cruise control vacuum hose broke?
Reply
Old Oct 14, 2014 | 08:09 AM
  #7  
ThatGuyOnTheGas's Avatar
Thread Starter
Full Member
 
Joined: Nov 2013
Posts: 54
Likes: 0
From: Fort Leonard Wood, Mo
The cruise vacuum hose isn't broke, I don't use cruise anyways. Line #1 comes from the cruise and then splits into a T
Reply
Old Oct 14, 2014 | 08:58 AM
  #8  
jjwalker's Avatar
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Ah, i see it now. Do you have an open vacuum nipple on the thermostat? Been many years since I had that piece of junk hooked up, but if I remember correctly that disconnected vacuum line you showed in the picture connects to it so the thermostat can keep the secondaries closed when the engine is cold.

If you don't know what the "thermostat" I am talking about is, look at the middle pic in your post. It's the yellow looking thing screwed into the throttle body just under and to the left of where the coolant hose connects. It has 2 vacuum nipples pointing down on it.
Reply
Old Oct 14, 2014 | 09:09 AM
  #9  
ThatGuyOnTheGas's Avatar
Thread Starter
Full Member
 
Joined: Nov 2013
Posts: 54
Likes: 0
From: Fort Leonard Wood, Mo
Okay, I got all the vacuum hoses reconnected, and I'm checking the Tps. It's level at 1220ohms at closed throttle, goes up to about 1325ohms at about 1/4 throttle and thats as high as it gets before it flatlines at 460ohms at WOT. I'm not sure what this means
Reply
Old Oct 14, 2014 | 09:13 AM
  #10  
ThatGuyOnTheGas's Avatar
Thread Starter
Full Member
 
Joined: Nov 2013
Posts: 54
Likes: 0
From: Fort Leonard Wood, Mo
All the hoses on the thermostat are connected. I didn't remove them. I let the throttle body sit on the housings to keep from having a bigger mess of vacuum lines to forget to hook back up
Reply
Old Oct 14, 2014 | 01:51 PM
  #11  
jjwalker's Avatar
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Originally Posted by ThatGuyOnTheGas
All the hoses on the thermostat are connected. I didn't remove them. I let the throttle body sit on the housings to keep from having a bigger mess of vacuum lines to forget to hook back up
Was i right?
Reply
Old Oct 14, 2014 | 09:44 PM
  #12  
ThatGuyOnTheGas's Avatar
Thread Starter
Full Member
 
Joined: Nov 2013
Posts: 54
Likes: 0
From: Fort Leonard Wood, Mo
The line coming off of the T went just under the thermostat, the other on the bottom end of the secondary fuel rail. SOO MUCH VACUUM LINE!! D: Either way, they're all hooked up now. Question though, I should see the tachometer jump as I crank it, right? I think I remember my 88 doing it, but this 91 doesn't. I can't get it to start if you couldn't tell ):
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
trickster
2nd Generation Specific (1986-1992)
25
Jul 1, 2023 04:40 PM
Kyo
2nd Generation Specific (1986-1992)
6
Apr 13, 2019 09:24 AM
dkwasherexd
Single Turbo RX-7's
21
May 27, 2017 04:51 AM
HDA
Build Threads
8
Nov 3, 2015 03:49 PM
pzr2
General Rotary Tech Support
1
Aug 15, 2015 08:29 PM




All times are GMT -5. The time now is 11:08 AM.